1. A mounting table for mounting a substrate thereon,

the mounting table includes:

a top plate part on which a substrate is placed;

a light irradiation mechanism having a plurality of light emitting elements, arranged to face the substrate placed on the top plate, and configured to heat the substrate by light from the light emitting elements; and

a flow path forming member joined to the back surface of the top plate so as to be interposed between the top plate and the light irradiation mechanism, the flow path forming member forming a refrigerant flow path between the flow path forming member and the top plate, the refrigerant flow path allowing a refrigerant capable of transmitting light from the light emitting element to flow therethrough, the flow path forming member allowing light from the light emitting element to transmit therethrough,

the top plate portion and the flow passage forming member are formed of materials having different thermal expansion coefficients from each other,

the mounting table further includes a temperature adjustment unit that adjusts the temperature of the flow path forming member using a material that can transmit light or light having a wavelength that can be absorbed by the flow path forming member.

2. The table of claim 1,

the table further includes:

a cooling unit that cools a driving unit that drives the light emitting element with a refrigerant; and

a control unit for controlling the temperature adjustment unit,

the control unit controls the temperature adjustment unit so that the flow path forming member is at a temperature at which the top plate does not warp, the temperature being calculated from the temperature of the top plate, the temperature of the coolant in the coolant flow path, and the temperature of the coolant in the cooling unit.

3. The table of claim 1,

the mounting table further includes a control unit for controlling the temperature adjustment unit,

the control unit controls the temperature adjustment unit so that the flow path forming member is at a temperature that does not warp the top plate portion, the temperature being predetermined for each operating condition of the mounting table.

4. The table according to any one of claims 1 to 3,

the temperature adjustment unit is a resistance heating heater formed of a material that can transmit light, and is provided on a surface of the flow path forming member on the side opposite to the top plate portion or inside the flow path forming member.

5. The table of claim 4,

the resistance heating heater is formed of ITO, IZO, ZnO, or IGZO.

6. An inspection apparatus, wherein,

the inspection apparatus comprises the mounting table according to any one of claims 1 to 5,

the inspection device inspects the electrical characteristics of the substrate by bringing the plurality of contact terminals into contact with the substrate mounted on the top plate.

7. A method for suppressing warpage of a mounting table on which a substrate is mounted, wherein,

the mounting table includes:

a top plate part on which a substrate is placed;

a light irradiation mechanism having a plurality of light emitting elements, arranged to face the substrate placed on the top plate, and configured to heat the substrate by light from the light emitting elements; and

a flow path forming member joined to the back surface of the top plate so as to be interposed between the top plate and the light irradiation mechanism, the flow path forming member forming a refrigerant flow path between the flow path forming member and the top plate, the refrigerant flow path allowing a refrigerant capable of transmitting light from the light emitting element to flow therethrough, the flow path forming member allowing light from the light emitting element to transmit therethrough,

the top plate portion and the flow passage forming member are formed of materials having different thermal expansion coefficients from each other,

the method for suppressing warpage of the mounting table adjusts the temperature of the flow path forming member by using a material that can transmit light or light having a wavelength that can be absorbed by the flow path forming member.

Background

Patent document 1 discloses a stage for mounting a substrate on which an electronic device is formed. The stage has a disk-shaped stage cover and a cooling unit having a coolant groove formed therein, the stage cover is in contact with the cooling unit via an O-ring, the coolant groove is covered by the stage cover to form a coolant flow path, and the O-ring seals the coolant to the coolant flow path. In the stage disclosed in patent document 1, the cooling unit and the cooling medium are transparent to light, and a light irradiation mechanism having a plurality of LEDs is provided so as to face the wafer through the stage cover and the cooling unit. The cooling unit is formed of glass and the stage cover is formed of SiC.

Patent document 1: japanese patent laid-open publication No. 2018-151369

Disclosure of Invention

Problems to be solved by the invention

The technology according to the present disclosure suppresses warpage of a mounting table formed by joining members formed of materials having different thermal expansion coefficients.

Means for solving the problems

One aspect of the present disclosure is a mounting table on which a substrate is mounted, the mounting table including: a top plate part on which a substrate is placed; a light irradiation mechanism having a plurality of light emitting elements, arranged to face the substrate placed on the top plate, and configured to heat the substrate by light from the light emitting elements; and a flow path forming member that is joined to the back surface of the top plate so as to be interposed between the top plate and the light irradiation mechanism, and that forms a refrigerant flow path between the top plate and the flow path forming member, through which a refrigerant that can transmit light from the light emitting element flows, the flow path forming member being capable of transmitting light from the light emitting element, the top plate and the flow path forming member being formed of materials having different thermal expansion coefficients, the mounting table further including a temperature adjustment unit that adjusts the temperature of the flow path forming member using a material that can transmit light or light having a wavelength that can be absorbed by the flow path forming member.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present disclosure, warpage of a mounting table formed by joining members formed of materials having different thermal expansion coefficients can be suppressed.

Drawings

Fig. 1 is a schematic perspective view showing a configuration of a probe as an inspection apparatus having a stage as a mounting table according to the present embodiment.

Fig. 2 is a schematic front view showing the structure of a probe as an inspection apparatus having a stage as a mounting table according to the present embodiment.

Fig. 3 is a plan view schematically showing the structure of a wafer.

Fig. 4 is a sectional view schematically showing the structure of the stage.

Fig. 5 is a plan view schematically showing the structure of the light irradiation mechanism.

Fig. 6 is a diagram schematically showing a configuration of a circuit for measuring the temperature of a wafer in the inspection apparatus of fig. 1.

Fig. 7 is a diagram for explaining a control example of the transparent heater.

Detailed Description

In a semiconductor manufacturing process, a plurality of electronic devices having a predetermined circuit pattern are formed on a substrate such as a semiconductor wafer (hereinafter referred to as "wafer"). The formed electronic device is inspected for electrical characteristics and the like, and sorted into good products and defective products. The electronic components are inspected by using an inspection apparatus in a state before the electronic components of the substrate are separated, for example.

An inspection apparatus called a prober or the like (hereinafter referred to as a "prober") includes a probe card having a plurality of probes and a mounting table on which a substrate is mounted. In the inspection, in a prober, each probe of a probe card is brought into contact with each electrode of an electronic device, and in this state, an electric signal is supplied from a tester provided on the upper portion of the probe card to the electronic device via each probe. Then, whether the electronic device is a defective product is screened based on the electric signals received by the tester from the electronic device via the probes.

In order to reproduce the mounting environment of the electronic component when the electrical characteristics of the electronic component are detected by such a probe, the temperature of the mounting table is controlled by a heater having a resistance heating element and a flow path through which a refrigerant flows, which are provided in the mounting table, to control the temperature of the substrate.

However, in recent years, electronic devices have been increasingly sophisticated and miniaturized, and the degree of integration has been increased, and the amount of heat generated during operation has particularly increased. Therefore, in the process of inspecting one electronic device, a thermal load may be applied to another electronic device adjacent to the substrate, and a failure may occur in the other electronic device.

Regarding this problem, patent document 1 discloses a mounting table as a stage described below. The stage disclosed in patent document 1 includes a disc-shaped stage cover and a cooling unit having a coolant groove formed therein, the stage cover is in contact with the cooling unit via an O-ring, the coolant groove is covered by the stage cover to form a coolant flow path, and the O-ring seals the coolant flow path. Further, a light irradiation mechanism having a plurality of LEDs is provided so as to face the wafer through the stage cover and the cooling unit, and since the cooling unit and the cooling medium are transparent, light from the LEDs reaches the stage cover through the cooling mechanism and the like. The light irradiation mechanism can locally irradiate the stage cover with light from the LED. With these configurations, the stage disclosed in patent document 1 cools the entire stage cover by the cooling structure, and irradiates the stage cover with light locally to heat the stage cover, thereby controlling only the temperature of a desired electronic component and cooling other electronic components.

Conventionally, SiC having a high thermal conductivity has been used for a material of a top plate portion of a stage, which is a stage cover, in consideration of easiness of heating of light from an LED, and glass, which is an inexpensive transparent member, has been used for a material of a flow path forming member forming a refrigerant flow path together with the top plate portion. As a material of the flow passage forming member, specifically, in order to maintain transparency with respect to light from the LED, glass having a thermal expansion coefficient different from that of SiC, which is a material of the top plate, has been used conventionally.

However, in order to seal the refrigerant flow path, the top plate and the flow path forming member may be bonded with epoxy resin or the like. When the bonding is performed using an epoxy resin or the like, if the material of the top plate portion and the material of the flow path forming member have different thermal expansion coefficients as described above, the stage may be warped when the inspection is performed at a temperature band significantly different from the temperature at the time of bonding. If the stage is warped in this manner, for example, the probes of the probe card cannot be brought into uniform contact with the substrate on the stage, and therefore the inspection quality may be adversely affected.

Accordingly, the technique according to the present disclosure suppresses warpage of the mounting table formed by joining members formed of materials having different thermal expansion coefficients.

Hereinafter, a mounting table, an inspection apparatus, and a method of adjusting warpage of a mounting table according to the present embodiment will be described with reference to the drawings. In the present specification and the drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description thereof is omitted.

Fig. 1 and 2 are a perspective view and a front view, respectively, showing the outline of the structure of a probe 1 as an inspection apparatus having a stage as a mounting table according to the present embodiment. Fig. 2 is a cross-sectional view showing a part of a storage chamber and a component to be built in a loader of the probe 1 of fig. 1.

The prober 1 of fig. 1 and 2 performs an inspection of electrical characteristics of a wafer W as a substrate and an inspection target in the present embodiment, specifically, electrical characteristics of each of a plurality of electronic devices (see reference numeral D in fig. 3 described later) formed on the wafer W. The probe 1 comprises: a housing chamber 2 for housing a wafer W during inspection; a loader 3 disposed adjacent to the storage chamber 2; and a tester 4 disposed so as to cover the storage chamber.

The housing chamber 2 is a hollow case and has a stage 10 on which a wafer W is placed. The stage 10 holds the wafer W by suction so that the position of the wafer W with respect to the stage 10 does not deviate. The stage 10 is provided with a moving mechanism 11 for moving the stage 10 in the horizontal direction and the vertical direction. The moving mechanism 11 includes a base 11a, the base 11a is made of a metal material such as stainless steel, and the stage 10 is disposed on the upper portion of the base 11a, and although not shown, the moving mechanism 11 includes a guide rail, a ball screw, a motor, and the like for moving the base 11 a. By the moving mechanism 11, the electrode on the surface of the wafer W is brought into contact with the probe 12a of the probe card 12, while the relative position between the probe card 12 and the wafer W, which will be described later, is adjusted.

A probe card 12 is disposed above the stage 10 of the housing chamber 2 so as to face the stage 10, and the probe card 12 includes a plurality of probes 12a as contact terminals. The probe card 12 is connected to the tester 4 via an interface 13. In the inspection of the electrical characteristics, the probes 12a are brought into contact with electrodes of electronic devices on the wafer W, and supply power from the tester 4 to the electronic devices through the interface 13, and transmit signals from the electronic devices to the tester 4 through the interface 13.

The loader 3 takes out the wafer W stored in the FOUP (not shown) as a transport container and transports the wafer W to the stage 10 of the storage chamber 2. The loader 3 receives the wafer W, for which the inspection of the electrical characteristics of the electronic device is completed, from the stage 10, and stores the wafer W in the FOUP.

The loader 3 also has a control unit 14 that performs various controls such as temperature control of the electronic device to be inspected. The control unit 14, which is also referred to as a basic unit or the like, is configured by a computer including a CPU, a memory, and the like, and includes a program storage unit (not shown). The program storage unit stores programs for controlling various processes of the probe 1. The program may be a program recorded on a computer-readable storage medium and loaded from the storage medium to the control unit 14. Part or all of the program may be implemented by dedicated hardware (circuit substrate).

The loader 3 further includes a potential difference measuring unit 15 that measures a potential difference at a potential difference generating circuit (not shown) of each electronic device. The potential difference generating circuit is, for example, a diode, a transistor, or a resistor. The potential difference measuring means 15 is connected to the interface 13 via a wiring 16, acquires a potential difference between the two probes 12a in contact with the two electrodes corresponding to the potential difference generating circuit, and transmits the acquired potential difference to the control unit 14. The connection structure of each probe 12a and the wiring 16 at the interface 13 will be described later. The control unit 14 is connected to the stage 10 via a wiring 17, and controls a light irradiation mechanism 140 described later and a flow rate control valve for adjusting the flow rate of the refrigerant flowing through the refrigerant flow path R described later. The control unit 14 and the potential difference measuring unit 15 may be provided in the housing chamber 2, and the potential difference measuring unit 15 may be provided in the probe card 12.

The tester 4 includes a test board (not shown) reproducing a part of a circuit configuration of a motherboard on which an electronic device is mounted. The test board is connected to a test computer 18 which determines whether the electronic device is good based on a signal from the electronic device. The tester 4 can reproduce circuit configurations of various kinds of motherboards by replacing the test board.

Furthermore, the probe 1 comprises a user interface section 19, which user interface section 19 is used for displaying information to the user for the user to input instructions. The user interface section 19 includes, for example, an input section such as a touch panel or a keyboard, and a display section such as a liquid crystal display.

In the probe 1 having the above-described components, the test computer 18 transmits data to the test board connected to the probes 12a via the electronic device at the time of inspecting the electrical characteristics of the electronic device. Then, the test computer 18 determines whether the transmitted data has been correctly processed by the test board based on the electrical signal from the test board.

Next, a wafer W to be inspected by the prober 1 will be described with reference to fig. 3. Fig. 3 is a plan view schematically showing the structure of the wafer W.

As shown in fig. 3, a plurality of electronic devices D are formed on the surface of the wafer W with a predetermined interval therebetween by performing etching processing and wiring processing on a substantially disk-shaped silicon substrate. An electrode E is formed on the surface of the wafer W, which is an electronic device D, and the electrode E is electrically connected to a circuit element inside the electronic device D. By applying a voltage to the electrode E, a current can flow to the circuit element inside each electronic device D. The size of the electronic device D is, for example, 10 to 30mm square in plan view.

Next, the structure of the stage 10 will be described with reference to fig. 4 and 5. Fig. 4 is a sectional view schematically showing the structure of the stage 10, and fig. 5 is a plan view schematically showing the structure of a light irradiation mechanism 140 described later.

As shown in fig. 4, the stage 10 is formed by stacking a plurality of functional units including a top plate 120 as a top plate portion. The stage 10 is mounted on a moving mechanism 11 (see fig. 2) for moving the stage 10 in the horizontal direction and the vertical direction via a heat insulating member 110. The heat insulating member 110 is used to thermally insulate the stage 10 from the moving mechanism 11, and is formed of, for example, a sintered body of cordierite having low thermal conductivity and thermal expansion coefficient. The base 11a of the moving mechanism 11 and the heat insulating member 110 are solid.

The stage 10 includes a top plate 120, a flow path forming member 130, and a light irradiation mechanism 140 in this order from above. The stage 10 is supported by the moving mechanism 11 through the heat insulating member 110 from below the light irradiation mechanism 140, in other words, from the back surface side of the light irradiation mechanism 140.

The top plate 120 is a member on which the wafer W is placed. In other words, the top plate 120 is a member having a wafer mounting surface, which is a substrate mounting surface on which the wafer W is mounted, on a front surface 120a thereof. Hereinafter, the surface 120a of the top plate 120, which is also the upper surface of the stage 10, may be referred to as a wafer mounting surface 120 a.

The top plate 120 is formed in a disc shape, for example. In addition, the top plate 120 is formed of a material having a small specific heat and a high thermal conductivity, for example, sic (silicon carbide). By forming the top plate 120 of such a material, the heating and cooling of the top plate 120 can be efficiently performed, and thus the wafer W placed on the top plate 120 can be efficiently heated and cooled. In the following, the top plate 120 is formed of SiC.

The Young's modulus of SiC is high, 300 GPa. Therefore, by forming the top plate 120 of SiC, an effect of preventing cracks and the like from occurring in the top plate 120 can also be obtained.

Further, suction holes (not shown) for sucking the wafer W are formed in the wafer mounting surface 120a of the top plate 120. In addition, a plurality of temperature sensors 121 are embedded in the top plate 120 at positions spaced apart from each other in a plan view.

The flow path forming member 130 is joined to the back surface of the top plate 120 so as to be interposed between the top plate 120 and the light irradiation mechanism 140, forms a refrigerant flow path R through which a refrigerant flows between the flow path forming member and the top plate 120, and is formed in a disc shape having substantially the same diameter as the top plate 120.

Further, a groove is formed in the back surface 120b of the top plate 120 to which the flow passage forming member 130 is attached, and the groove is covered with the flow passage forming member 130 to form the refrigerant flow passage R. In the prober 1, the top plate 120 is cooled by the refrigerant flowing through the refrigerant passage R, thereby cooling the wafer W placed on the top plate 120, that is, on the stage 10, and specifically, cooling the electronic components formed on the wafer W.

Further, the top plate 120 is formed with a supply port 122 and a discharge port 123 that communicate with the refrigerant flow path R. A supply pipe 160 for supplying the refrigerant to the refrigerant flow path R is connected to the supply port 122, and a discharge pipe 161 for discharging the refrigerant from the refrigerant flow path R is connected to the discharge port 123. The supply pipe 160 is provided with a flow rate control valve 162 that controls the flow rate of the refrigerant supplied to the refrigerant flow path R.

As the refrigerant flowing through the refrigerant flow path R, a material that can transmit light (specifically, light from an LED141 described later), for example, a fluorine-based inactive liquid (registered trademark), novec (registered trademark), or the like is used, and is supplied to the refrigerant flow path R through the supply pipe 160 by a pump (not shown) provided outside the probe 1. The control unit 14 controls the operation of the flow control valve 162 and the like for adjusting the flow rate of the refrigerant.

As a material of the flow passage forming member 130 constituting the refrigerant flow passage R, a material that can transmit light (specifically, light from an LED141 described later) is used. In the following examples, the flow path forming member 130 is formed of glass.

The flow passage forming member 130 and the top plate 120 are joined to each other so as to seal the refrigerant in the refrigerant flow passage R. The joining is performed using, for example, an epoxy resin, and more specifically, the joining is performed by applying an epoxy resin between the flow path forming member 130 and the top plate 120 and heating the flow path forming member 130 and the top plate 120 to a predetermined temperature (for example, 100 ℃) while pressing them together.

The light irradiation mechanism 140 is disposed so as to face the wafer W placed on the wafer placement surface 120a of the top plate 120 through the flow path forming member 130.

The light irradiation mechanism 140 includes a plurality of LEDs 141 as light emitting elements directed toward the wafer W, and heats the wafer W by light from the LEDs 141. Specifically, the light irradiation mechanism 140 includes a plurality of LED units U each formed by unitizing a plurality of LEDs 141, and a base 142 on which the LED units U are mounted. For example, as shown in fig. 5, the LED units U of the light irradiation mechanism 140 cover substantially the entire surface of the base 142 with units U1 having a square shape in plan view and covering the outer periphery thereof and units U2 having a non-square shape in plan view, the units U being arranged in the same number and in the same manner as the electronic devices D (see fig. 3) formed on the wafer W. Thus, at least the entire contact portion of the top plate 120 with the wafer W can be irradiated with light from the LED141 of the LED unit U.

Each LED141 irradiates light toward the wafer W. In this example, each LED141 emits near-infrared light. Light emitted from the LED141 (hereinafter, sometimes abbreviated as "LED light") passes through the flow path forming member 130 of the stage 10 formed of a light transmitting member. The light having passed through the flow passage forming member 130 passes through the refrigerant that flows through the refrigerant flow passage R of the stage 10 and is capable of transmitting light, and is incident on the top plate 120.

The base 142 is formed in a disc shape having substantially the same diameter as the top plate 120 in a plan view. As shown in fig. 4, the base 142 has a recess 142a formed in a surface thereof, and the LED141 is mounted in the recess 142 a. The inside of the concave portion 142a may be filled with a material that can transmit LED light.

The base 142 has a cooling water passage 142b formed in a portion thereof on the back surface side of the recess 142a, and the cooling water passage 142b is configured to flow cooling water as a coolant for cooling the LED 141. The base 142 is formed of a metal material such as Al.

The light irradiation mechanism 140 includes a drive circuit board 143 for driving the LEDs 141, and a support member 144 on which the drive circuit board 143 is mounted.

The support member 144 has a recess 144a formed in a surface thereof, and the drive circuit board 143 is mounted in the recess 144 a. The support member 144 is formed of a metallic material such as Al.

The light irradiation mechanism 140 controls the LED light incident on the top plate 120 on which the wafer W is placed, in units of LED units U. Therefore, the light irradiation mechanism 140 can irradiate LED light only to an arbitrary portion of the top plate 120 or can make the intensity of the irradiated light different from that of other portions at the arbitrary portion. Therefore, the wafer W placed on the top plate 120 can be locally heated by the light irradiation mechanism 140, and the heating degree of the wafer W can be locally changed.

Also, the stage 10 has a transparent heater 150. The transparent heater 150 is an example of a temperature adjusting portion that adjusts the temperature of the flow path forming member 130 using a substance that can transmit light. The transparent heater 150 is a resistance heating heater formed of a conductive material that can transmit LED light (e.g., light having a wavelength of 850 nm). As the conductive material, for example, ito (indium Tin oxide), izo (indium Zinc oxide), zno (Zinc oxide), and IGZO (oxide semiconductor including indium (In), gallium (Ga), and Zinc (Zn)) can be used. The transparent heater 150 is provided on the flow path forming member 130, specifically, on the back surface of the flow path forming member 130 opposite to the top plate 120. In this case, the transparent heater 150 is formed by, for example, a sputtering method or a vapor deposition method. For example, the transparent heater 150 is formed in advance by the sputtering method or the like before the top plate 120 and the flow channel forming member 130 are joined together.

The formation position of the transparent heater 150 is not limited to the back surface of the flow path forming member 130, and may be the inside of the portion on the back surface side of the flow path forming member 130.

A temperature sensor (not shown) for measuring the temperature of the flow path forming member 130 is provided around the transparent heater 150.

The transparent heater 150 heats the flow passage forming member 130 in such a manner that a difference in thermal expansion between the top plate 120 formed of SiC and the flow passage forming member 130 formed of glass having a thermal expansion coefficient different from that of SiC can be absorbed. In other words, the transparent heater 150 heats the flow path formation member 130 so as not to warp the stage 10, and more specifically, heats the flow path formation member 130 so as not to warp the top plate 120.

The heating of the flow path forming member 130 by the transparent heater 150, that is, the amount of energization to the transparent heater 150 is controlled by the control unit 14.

The control unit 14 controls the transparent heater 150 so that the temperature of the flow path forming member 130 measured by the above-described temperature sensor (not shown) provided around the transparent heater 150 becomes the temperature T of the flow path forming member 130 that does not warp the top plate 120_H. Temperature T for flow path forming member 130 that does not warp top plate 120_HFor example, the calculation is performed by the control unit 14 based on the operating conditions of the stage 10. More specifically, the temperature T of the flow path forming member 130 that does not warp the top plate 120_HBased on the temperature T of the top plate 120_TPTemperature T of refrigerant flowing through refrigerant passage R_coolAnd the temperature T of the cooling water flowing through the cooling water path 142b for cooling the LED141_LED-CAnd is calculated by the control unit 14. Pre-obtaining T used for the calculation_HAnd T_TP、T_coolAnd T_LED-CThe relation between, i.e. the function f (T)_TP，T_cool，T_LED-C) And stored in a storage unit (not shown).

T_H＝f(T_TP，T_cool，T_LED-C)

Further, with respect to the above temperature T_TPFor example, an average value of the detection results detected by the temperature sensor 121 can be used. Also for measuring the above-mentioned temperature T_coolThe above temperature T_LED-CAnd a temperature sensor is arranged, if the temperature T is higher than the preset temperature T_coolThe above temperature T_LED-CIf the temperature T is constant, the temperature T may be set_coolThe above temperature T_LED-CIs stored in a storage unit (not shown) in advance, and calculates the temperature T_HThe data is read from the memory.

In the probe 1, heating by the light from the light irradiation mechanism 140 and heat absorption by the refrigerant flowing through the refrigerant flow path R are controlled so that the temperature of the electronic device D to be inspected formed on the wafer W on the stage 10 becomes a target temperature and is constant. In order to perform this temperature control, the temperature of the electronic device D is measured at the probe 1.

Fig. 6 is a diagram schematically showing the configuration of a circuit for measuring the temperature of the electronic device D of the probe 1.

In the prober 1, as shown in fig. 6, each probe 12a is connected to the tester 4 by a plurality of wires 20 arranged at the interface 13. Further, of the wirings 20, two wirings 20 connecting the tester 4 and two probes 12a which are in contact with two electrodes E of a potential difference generating circuit (for example, a diode) of the electronic device D are provided with relays 21, respectively.

Each relay 21 is configured to be capable of switching and transmitting the potential of each electrode E to either the tester 4 or the potential difference measuring unit 15. For example, when the electrical characteristics of the electronic device D are inspected, the relays 21 apply a mounting voltage to the electrodes E, and then transmit the potential of the electrodes E to the potential difference measuring unit 15 at a predetermined timing. In the above-described potential difference generating circuit, the potential difference generated when a current flows varies depending on the temperature. Therefore, the temperature of the electronic device D can be measured in real time during the inspection based on the potential difference of the potential difference generation circuit of the electronic device D, that is, based on the potential difference between the two electrodes E (probes 12a) of the potential difference generation circuit. In the probe 1, the potential difference measuring means 15 obtains the potential difference of the potential difference generating circuit of the electronic device D based on the potentials of the electrodes E transmitted from the relays 21, and then transmits the obtained potential difference to the control unit 14. The control unit 14 measures the temperature of the electronic device D based on the transmitted potential difference and the temperature characteristics of the potential difference generation circuit.

The method of measuring the temperature of the electronic device D is not limited to the above method, and other methods may be used as long as the temperature of the electronic device D can be measured.

Next, an example of processing performed on the wafer W using the prober 1 will be described.

First, the wafer W is taken out from the FOUP of the loader 3, transported toward the stage 10, and placed on the wafer placement surface 120a of the top plate 120. Next, the stage 10 is moved to a predetermined position.

Then, all the LEDs 141 of the light irradiation mechanism 140 are turned on, and the light output from the LEDs 141 and the flow rate of the refrigerant flowing through the refrigerant flow path R are adjusted based on the information acquired from the temperature sensor 121 of the top plate 120 so that the temperature of the top plate 120 becomes uniform over the surface.

Thereafter, the stage 10 is moved so that the probes 12a provided above the stage 10 are brought into contact with the electrodes E of the electronic devices D to be inspected on the wafer W.

In this state, the potential difference of the potential difference generating circuit of the electronic device D to be inspected is acquired by the potential difference measuring unit 15. Then, the temperature of the top plate 120 having been made uniform in the plane is made substantially equal to the temperature of the electronic device D to be inspected, and the potential difference is corrected, that is, the information of the temperature characteristic of the potential difference is corrected.

Thereafter, a signal for inspection is input to each probe 12 a. Thereby, the inspection of the electronic device D is started. In the inspection, based on the information of the potential difference generated by the potential difference generating circuit of the electronic device D to be inspected, the light output from the LED141 of the LED unit U corresponding to the device, that is, the applied voltage of the LED141 is controlled so that the temperature of the electronic device D becomes, for example, a test temperature or a target temperature. The temperature and the flow rate of the refrigerant in the refrigerant flow path R are, for example, values corresponding to a test temperature or a target temperature of the electronic device D to be inspected, and are set to be constant.

After that, the above-described steps of correcting and inspecting the potential difference of the potential difference generating circuit are repeated until the inspection of all the electronic devices D is completed.

During the steps of correcting and inspecting the potential difference of the potential difference generating circuit, the flow path forming member 130 is heated by the transparent heater 150 so that the top plate 120 is not warped. For example, the control unit 14 is based on the temperature T of the top plate 120 measured by the temperature sensor 121_TPAverage value of (1), and refrigerant flowing in the refrigerant passage RTemperature T of refrigerant_coolAnd the temperature T of the cooling water flowing through the cooling water path 142b for cooling the LED141_LED-CThe temperature T of the flow path forming member 130 which does not warp the top plate 120 is calculated_H. Then, the control unit 14 controls the transparent heater 150 so that the temperature of the flow path forming member 130 measured by a temperature sensor (not shown) provided around the transparent heater 150 becomes the temperature T_H。

Therefore, in the correction and inspection of the potential difference generating circuit, since the top plate 120 does not warp, the wafer W sucked and held on the top plate 120 is uniformly brought into contact with the probes 12a of the probe card 12. Thus, the above correction and inspection can be accurately performed.

The process performed on the wafer W using the prober 1 may include a step of imaging the surface of the wafer W on the top plate 120 by an imaging device (not shown) provided in the housing chamber 2. For example, in the step of aligning the probe 12a with the wafer W and the step of checking the trace of the probe 12a after inspection, that is, the needle mark, the electrode E on the wafer W is imaged by the imaging device. In the step of performing such imaging, the LED141 may not be turned on. In the case where the LED141 is not lit, the top plate 120 may be warped. When the top plate 120 is warped during imaging, the focus may not match the electrode of the top plate 120 unless the height of the imaging device is changed. Therefore, if the top panel 120 is warped, the above-described alignment step and the step of confirming the needle mark are prolonged. Therefore, in these steps, the control unit 14 controls the transparent heater 150 so that the temperature of the flow path forming member 130 measured by a temperature sensor (not shown) provided around the transparent heater 150 becomes the temperature T of the flow path forming member 130 that does not warp the top plate 120_HAnd (4) finishing. This can prevent these steps from being lengthened.

As described above, in the present embodiment, the stage 10 includes: a top plate 120 on the surface of which a wafer W is placed; a flow path forming member 130 joined to the back surface 120b of the top plate 120, forming a refrigerant flow path R through which a refrigerant capable of transmitting light flows between the flow path forming member 130 and the top plate 120, the flow path forming member 130 being capable of transmitting light; and a light irradiation mechanism 140 having a plurality of LEDs 141, disposed so as to face the wafer W placed on the top plate 120 with the flow path forming member 130 interposed therebetween, and configured to heat the wafer W by light from the LEDs 141. Therefore, the stage 10 cools the entire top plate 120 by the refrigerant flowing through the refrigerant flow path R, and heats the top plate 120 by locally irradiating the LED light thereto, so that it is possible to control only the temperature of the desired electronic device D and cool the other electronic devices. In the stage 10, the top plate 120 and the flow path forming member 130 are formed of materials having different thermal expansion coefficients, and when the stage 10 is likely to be warped, specifically, when the top plate 120 is likely to be warped, the transparent heater 150 is provided as a temperature adjusting portion for adjusting the temperature of the flow path forming member 130 by a light-transmittable substance. Thus, according to the present embodiment, by adjusting the temperature of the flow path forming member 130 using the transparent heater 150, the top plate 120 can be prevented from being warped. In addition, according to the present embodiment, since the top plate 120 is not warped, the plurality of probes 12a can be brought into uniform contact with the electronic device D, and therefore, electrical characteristics inspection or the like using the probe card 12 having the plurality of probes 12a can be accurately performed. Moreover, since the top plate 120 is not warped regardless of the temperature of the top plate 120, i.e., regardless of the inspection temperature, the stage 10 can be used in a wide inspection temperature range.

In the above example, the control unit 14 is based on the temperature T of the top plate 120_TPTemperature T of refrigerant flowing through refrigerant passage R_coolAnd the temperature T of the cooling water flowing in the cooling water path 142b cooling the LED141_LED-CUnder the operating conditions of the stage 10, the temperature T of the flow path forming member 130 is calculated so as not to warp the top plate 120_H. Specifically, the control unit 14 bases on the function f (T)_TP，T_cool，T_LED-C) Calculating and obtaining the temperature T_H. The above temperature T_HThe operating conditions of the stage 10 used for the calculation of (2) are not limited to the combination, and may be, for example, only the temperature T of the top plate 120_TPAnd the temperature of the refrigerant flowing in the refrigerant passage RT_cool. In other words, the temperature T based on the top plate 120 may also be used_TPAnd the temperature T of the refrigerant flowing through the refrigerant passage R_coolFunction f (T) of_TP，T_cool) The control part 14 controls the temperature T_HAnd (4) calculating.

In the above example, the temperature T of the flow path forming member 130 that does not warp the top plate 120 is calculated and acquired based on the operating conditions of the stage 10_H. The above temperature T_HThe acquisition method of (2) is not limited to this, and may be, for example, the following method. That is, the temperature T of the flow path forming member 130 that does not warp the top plate 120 is predetermined for each operating condition of the stage 10_HAnd stored in a storage unit (not shown). Then, at the time of inspection, the control unit 14 reads out and acquires the temperature T from the storage unit, which is matched with the operation condition of the stage 10 at the time of inspection_H. More specifically, for example, the temperature T is predetermined to be different between a case where the LED141 is turned on and a case where the LED141 is not turned on_HAnd stored in a storage unit, and the control unit 14 may select the temperature T read from the storage unit according to whether or not the LED141 is turned on_H. In such a method, the warpage of the top plate 120 can be prevented regardless of the magnitude of the predicted warpage amount of the top plate 120.

Fig. 7 is a diagram for explaining a control example of the transparent heater 150.

As shown in fig. 7, the flow path forming member 130 is divided into a plurality of (5 in this example) areas a, and the control section 14 can control the amount of heating of the flow path forming member 130 by the transparent heater 150 for each area a. Specifically, for example, a temperature sensor (not shown) is provided in advance around the transparent heater 150 for each region a of the flow path forming member 130. Then, for each area a, the control unit 14 calculates the temperature T of the top plate 120 corresponding to the area a based on the temperature measured by the temperature sensor 121_TPTemperature T of refrigerant_coolTemperature T of cooling water_LED-CAccording to the function f (T) described above_TP，T_cool，T_LED-C) Calculating the temperature T of the flow passage forming member 130 that does not warp the top plate 120_H. The control unit 14 controls the transparent heater 150 so that the temperature of each region a measured by the temperature sensor (not shown) provided in each region a of the flow path forming member 130 becomes the temperature T calculated for each region a_H。

This can prevent the top plate 120 from being locally heated strongly and thus the top plate 120 from being locally warped.

In the above example, the transparent heater 150 is used as the temperature adjustment unit for adjusting the temperature of the flow path forming member 130, but the temperature adjustment unit is not limited thereto. For example, the temperature adjustment unit may include a light source that emits light having a wavelength different from that of the light from the LED141, specifically, a light source that emits light having a wavelength that can be absorbed by the flow path forming member 130, and the temperature adjustment may be performed by heating the flow path forming member 130 using the light. The temperature adjustment unit may be a unit that cools the flow path forming member 130, and may be a unit that uses a gas (carbonic acid (CO)) that can transmit light₂) Gas, etc.) to cool the back surface of the flow passage forming member 130. In this case, carbonic acid (CO) is supplied to the recess 142a of the susceptor 142₂) A gas for cooling, such as a gas. Therefore, the LEDs 141 can be cooled by the cooling gas, and the life of the LEDs 141 can be prolonged.

For example, in the above example, the refrigerant channel is formed by forming the refrigerant channel in the back surface of the top plate and covering the refrigerant channel with the channel forming member. Alternatively, the refrigerant channel may be formed by forming a refrigerant channel in the surface of the channel forming member and covering the refrigerant channel with a flat top plate.

The stage according to the present disclosure may be provided in a device other than the inspection device such as a prober, for example, a film deposition device, an etching device, a doping device, or the like, as long as the warpage of the wafer W may adversely affect the process result.

The presently disclosed embodiments are to be considered in all respects as illustrative and not restrictive. The above-described embodiments may be omitted, replaced, or modified in various ways without departing from the scope of the claims and the gist thereof.