Inspection device, position adjustment unit, and position adjustment method

Abstract

To enable the initial alignment of a probe with respect to an electrode pad to be adjusted with high accuracy, without relying on an operator's sense-based operation method.SOLUTION: An inspection device for inspecting electrical characteristics of a test piece using a contact piece which is electrically contacted with an electrode of the test piece, comprises: a position adjustment unit that includes the contact piece, a position adjustment part for adjusting a tip position of the contact piece and a load detection part for detecting a load value of contact between the contact piece and the electrode; a position derivation part for deriving an initial position of the contact piece in a specific direction on the basis of a relation between a contact displacement amount of the contact piece in a specific direction and the load value of the contact between the contact piece and the electrode; and a movement execution part for moving the tip position of the contact piece on the basis of the initial position in the specific direction having been derived by the position derivation part.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an inspection apparatus, a position adjustment unit, and a position adjustment method, and can be applied to, for example, an inspection apparatus for inspecting the electrical characteristics of semiconductor integrated circuits on a semiconductor wafer.

Background Art

[0002] For example, there is an inspection apparatus for individually inspecting the electrical characteristics of a specific device among semiconductor integrated circuits (devices) formed on a semiconductor wafer (see Patent Document 1).

[0003] Although there are various types of this kind of inspection apparatus, as illustrated in FIGS. 5 and 6, there is an inspection apparatus including a position adjustment unit in which an operator manually finely adjusts the tip position of a probe.

[0004] As illustrated in FIG. 7, the position adjustment unit 9 of a conventional inspection apparatus has an X knob 91 for finely adjusting the X-direction position of a probe 97, a Y knob 92 for finely adjusting the Y-direction position, and a Z knob 93 for finely adjusting the Z-direction position. The operator operates the X knob 91, the Y knob 92, and the Z knob 93 to finely adjust the position of the probe 97 so that the tip of the probe 97 contacts the electrode pad of the device.

[0005] Hereinafter, with reference to FIG. 8, a method for initially setting the probe position with respect to the electrode pad of a device will be briefly described.

[0006] First, the operator recognizes the electrode pad 80 of the device and the probe 97 using a microscope, a camera, or the like. The operator operates the X knob 91 and the Y knob 92 to align the position of the probe 97 on the XY plane (see FIG. 8(A)).

[0007] For example, FIG. 8(A) is a plan view of the upper surface of the electrode pad 80 as seen from above. When the tip position of the probe 97 is not at the approximate center of the electrode pad 80 (see FIG. 8(A-1)), the operator operates the X knob 91 and the Y knob 92 to move the tip of the probe 97 in the two-dimensional direction so that the tip position of the probe 97 becomes the approximate center position of the electrode pad 80 (see FIG. 8(A-2)).

[0008] Next, the operator operates the Z knob 93 to lower the tip position of the probe 97 in the Z direction. At this time, the tip position of the probe 97 is lowered until the tip of the probe 97 contacts the electrode pad 80 (see FIG. 8(B-1)). Further, until the tip of the probe 97 slides on the surface of the electrode pad 80, the operator operates the Z knob 93 to gradually lower the position of the probe 97 little by little (see FIG. 8(B-2)).

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0010] In recent years, wiring patterns on semiconductor wafers and electrode pads of devices have been continuously miniaturized. In proportion to this, the alignment of probes that play the role of transmitting and receiving electrical signals has also become more difficult. Therefore, there is a need for an inspection apparatus that can align probes with high precision by a simpler operation method than in the past.

[0011] However, as described above, all of the initial setting methods for the probe position are based on the operator's sense. In particular, regarding the alignment of the probe in the Z direction, it is necessary to capture a movement of about several microns (μm).

[0012] For example, if the Z-direction alignment of the probe is not performed correctly, there is a risk of causing damage to the probe or the electrode pad, and it may also affect the inspection quality of the device.

[0013] Therefore, there is a need for an inspection apparatus, a position adjustment unit, and a position adjustment method that can accurately adjust the initial alignment of the probe with respect to the electrode pad, rather than an operation method based on the operator's sense.

Means for Solving the Problem

[0014] To solve such a problem, a first aspect of the present invention provides an inspection apparatus for inspecting electrical characteristics of a test object using a contact that is electrically contacted with an electrode of the test object, comprising: (1) a position adjustment unit having a contact, a position adjustment unit for adjusting the tip position of the contact, and a load detection unit for detecting a contact load value between the contact and the electrode; and (2) Indicating the movement amount of the contact in a specific direction a position derivation unit that derives an initial position based on the relationship between the contact displacement amount and the contact load value of the contact and the electrode, and (3) a movement execution unit that moves the tip position of the contact based on the initial position in a specific direction derived by the position derivation unit, Proportion characterized in that. Indicating the physical initial contact position of the contact with the electrode To the initial position , Make the physical initial contact of the contact with the electrode 、 (4) When the contact load value becomes equal to or greater than the threshold value, the position derivation unit measures the measurement results of the contact load value and the contact displacement amount at that time, and then measures the measurement results of the contact load value and the contact displacement amount when the contact displacement amount of the contact is slightly changed. The initial position is derived using the load change value per unit length derived using the two measurement results and the measurement results

[0015] A second aspect of the present invention provides a position adjustment unit for adjusting the tip position of a contact that is electrically contacted with an electrode of a test object, comprising: (1) a position adjustment unit for adjusting the tip position of the contact; (2) a load detection unit for detecting a contact load value between the contact and the electrode; and (3) Indicating the movement amount of the contact in a specific direction a position derivation unit that derives an initial position based on the relationship between the contact displacement amount and the contact load value of the contact and the electrode, and (4) a movement execution unit that moves the tip position of the contact based on the initial position in a specific direction derived by the position derivation unit, Proportion characterized by having. Indicating the physical initial contact position of the contact with the electrode To the initial position , Make the physical initial contact of the contact with the electrode , (5) When the contact load value becomes equal to or greater than the threshold value, the position derivation unit measures the measurement results of the contact load value and the contact displacement amount at that time, and then measures the measurement results of the contact load value and the contact displacement amount when the contact displacement amount of the contact is slightly changed. The initial position is derived using the load change value per unit length derived using the two measurement results and the measurement results ​​​​​​​​

[0016] The third invention is a position adjustment unit having a contact, a position adjustment unit for adjusting the tip position of the contact, and a load detection unit for detecting the contact load value between the contact and the electrode of the object to be inspected, and is a position adjustment method for adjusting the tip position of the contact that makes electrical contact with the electrode, comprising: (1) a position derivation unit Indicating the movement amount of the contact in a specific direction derives an initial position based on the relationship between the contact displacement amount and the contact load value of the contact and the electrode, and (2) a movement execution unit moves the tip position of the contact based on the initial position in a specific direction derived by the position derivation unit Proportion based on the relationship between Indicating the physical initial contact position of the contact with the electrode and is characterized by To the initial position moving , Make the physical initial contact of the contact with the electrode, and (3) when the contact load value becomes equal to or greater than the threshold value, the position derivation unit measures the measurement results of the contact load value and the contact displacement amount at that time, and then measures the measurement results of the contact load value and the contact displacement amount when the contact displacement amount of the contact is slightly changed. The initial position is derived using the load change value per unit length derived using the two measurement results and the measurement results it.

Effect of the Invention

[0017] According to the present invention, the initial alignment of the probe with respect to the electrode pad can be adjusted with high precision.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Embodiments for Carrying Out the Invention

[0019] (A) Embodiment Hereinafter, embodiments of the inspection apparatus, the position adjustment unit, and the position adjustment method according to the present invention will be described in detail with reference to the drawings.

[0020] (A-1) Configuration of the Embodiment (A-1-1) Inspection Apparatus The inspection apparatus according to this embodiment basically has the same or corresponding configuration as an existing inspection apparatus. Therefore, also in this embodiment, the configuration of the inspection apparatus will be described with reference to FIGS. 5 and 6.

[0021] FIG. 5 is a configuration diagram showing a schematic configuration of the inspection apparatus according to the embodiment. FIG. 6 is a plan view when the position adjustment unit of the inspection apparatus according to the embodiment is viewed from above.

[0022] In FIG. 5, an inspection apparatus 1 according to the embodiment includes a housing 20, and a plurality of position adjustment units 10, a stage 21, and a stage drive unit 22 are provided inside the housing 20. Further, the inspection apparatus 1 includes a microscope 23.

[0023] The inspection apparatus 1 inspects the electrical characteristics of a semiconductor integrated circuit (device) formed on a semiconductor wafer placed on the upper surface of the stage 21.

[0024] In FIG. 5, most of the components of the inspection apparatus 1 are housed inside the housing 20, and a state where the housing 20 of the inspection apparatus 1 is placed on a workbench 5 is shown.

[0025] The housing 20 of the inspection apparatus 1 has a space inside, and a plate member 25 is provided inside the housing 20. The housing 20 is divided into an upper stage portion 26, which is an upper internal space, and a lower stage portion 27, which is a lower internal space, with the plate member 25 in between.

[0026] In the lower part 27 of the housing 20, a stage 21 for placing a semiconductor wafer and a stage driving unit 22 for driving the stage 21 are provided. Further, a plurality of position adjustment units 10 are provided in the upper part 26 of the housing 20.

[0027] The plate member 25 provided in the housing 20 is provided with a circular opening 251, and a plurality of position adjustment units 10 are arranged on the periphery of the opening 251. As illustrated in FIG. 6, each position adjustment unit 10 can electrically contact the probe 17 with the electrode pad of the device of the semiconductor wafer placed on the stage 21 through the opening 251.

[0028] Before the inspection is carried out, the inspection apparatus 1 performs initial alignment (first contact) of the probe 17 in order to electrically contact the probe 17 of each position adjustment unit 10 with the electrode pad of the device on the semiconductor wafer.

[0029] The inspection apparatus 1 includes a microscope 23 for an operator to visually recognize the fine devices on the semiconductor wafer. Note that the inspection apparatus 1 may include a camera (imaging device) such as a CCD camera instead of or in addition to the microscope 23, and display an image captured by the camera on a display unit such as a display.

[0030] During the inspection, the inspection apparatus 1 applies an electrical signal to the electrode pad of the device via the probe 17 of the position adjustment unit 10. On the other hand, when the device outputs an electrical signal, the electrical signal is applied to the inspection apparatus 1 via the probe 17. The inspection apparatus 1 inspects the electrical characteristics of the device based on the value of the electrical signal to the device and / or the value of the electrical signal from the device.

[0031] (A-1-2) Position Adjustment Unit FIG. 1 is an external perspective view showing the configuration of the position adjustment unit 10 according to the embodiment.

[0032] In FIG. 1, the position adjustment unit 10 includes a main body 100, an X-direction position adjustment unit (hereinafter referred to as "X knob") 11, a Y-direction position adjustment unit (hereinafter referred to as "Y knob") 12, a Z-direction position adjustment unit (hereinafter referred to as "Z knob") 13, a Z-knob drive unit 18, a load cell 19, an isolator 15, an arm support 14, an L-arm portion 16, and a probe 17.

[0033] The position adjustment unit 10 adjusts the position of a cantilever-type probe provided with a linear probe 17 at the tip of the L-arm portion 16, and electrically contacts the probe 17 with the electrode pads of the devices on the semiconductor wafer. Since the position adjustment unit 10 adjusts the position of the probe 17 by an operation by an operator, it is also called a manipulator.

[0034] Note that the position adjustment unit 10 is not limited to the configuration illustrated in FIG. 1 as long as it includes a cantilever-type probe. For example, instead of the L-arm portion 16, a linear arm portion may be provided, and the linear arm portion may support the probe 17. In any case, the position adjustment unit 10 is configured to adjust the position of the cantilever-type probe.

[0035] The probe 17 is formed of a conductive material and is a contact that electrically contacts the surface of the electrode pad of the device. The probe 17 is a linear contact. One end of the probe 17 is supported by the L-arm portion 16, and the other end of the probe 17 (also referred to as the "tip end") contacts the electrode pad. Therefore, the probe 17 is a cantilever-type probe.

[0036] The L-arm portion 16 is a support member that supports the probe 17. The L-arm portion 16 is formed of a conductive material. One end (for example, the lower end) of the L-arm portion 16 supports the probe 17, and the other end (for example, the upper end) is connected to a wiring (not shown) that propagates an electrical signal to the inspection device 1 side.

[0037] The arm support portion 14 is a member that supports the L-arm portion 16. In this example, the arm support portion 14 is provided at one end of the isolator 15. For example, the arm support portion 14 has a groove portion that supports a portion of the member extending in the vertical direction (Z direction) of the L-arm portion 16, and the vertical member of the L-arm portion 16 is fitted into and supported by this groove portion. to It has a groove portion that supports a portion of the member extending in the vertical direction of the L-arm portion 16, and the vertical member of the L-arm portion 16 is fitted into and supported by this groove portion.

[0038] The isolator 15 is formed of an insulating material. The isolator 15 is interposed between the arm support portion 14 and the load transducer 19 to prevent energization to the load transducer 19 and the main body portion 100 side during inspection.

[0039] The load transducer 19 converts the load amount (load value) acting on the cantilever type probe 17 into an electrical signal and gives the signal value to the control portion 243 of the inspection apparatus 1.

[0040] The load transducer 19 type may be any device that can measure the magnitude of the force (load amount) when the tip of the probe 17 of the cantilever is in contact with the electrode pad. For example, a load cell or the like that detects a load can be applied. The load transducer 19 is provided between the main body portion 100 and the L-arm portion 16 and.

[0041] For example, as illustrated in FIG. 1, the load transducer 19 as a load cell has two strain gauges 191 and 192 on the upper surface and two strain gauges 193 and 194 on the lower surface. When pressure is applied at the time of contact between the probe 17 and the electrode pad and the load transducer 19 is deformed (for example, bent), the strain gauges 191 to 194 are also deformed, and the resistance values of the strain gauges 191 to 194 change. Therefore, when an input voltage is applied to the load transducer 19, a voltage corresponding to the change in the resistance values of the strain gauges 191 to 194 is output. Accordingly, based on the value of the output voltage from the load transducer 19, the magnitude of the force at the time of contact between the probe 17 and the electrode pad is measured.

[0042] The X knob 11, Y knob 12, and Z knob 13 are adjustment knobs of a position adjustment mechanism for finely adjusting the tip position of the probe 17. The X knob 11 is an adjustment knob of the fine adjustment mechanism in the X direction, and the Y knob 12 is an adjustment knob of the fine adjustment mechanism in the Y direction.

[0043] The Z knob 13 is an adjustment knob of the fine adjustment mechanism in the Z direction, and the Z knob 13 is driven by receiving a driving force from a Z knob driving unit 18 such as a motor. That is, the X knob 11 and Y knob 12 are manually operated by an operator in the same manner as a conventional position adjustment unit, but the Z knob 13 is automatically moved by the Z knob driving unit 18. In other words, the position adjustment unit 10 automatically finely adjusts at least the Z-direction position of the probe 17.

[0044] FIG. 2 is a configuration diagram showing the configuration of the fine adjustment process in the Z direction in the embodiment.

[0045] In FIG. 2, the configuration of the fine adjustment process in the Z direction includes a load cell 19, a differential amplifier circuit 241, an A / D converter 242, a control unit 243, a motor control unit 244, and a Z knob driving unit 18.

[0046] When an input voltage is applied to the load cell 19, the resistance values of the strain gauges 191 to 194 change due to the deformation of the strain gauges 191 to 194, and an output voltage that can change accordingly is output.

[0047] The differential amplifier circuit 241 inputs two voltage values output from the load cell 19, amplifies the difference value obtained by differentiating the two voltage values with a differential gain, and outputs the result to the A / D converter 242.

[0048] The A / D converter 242 converts the output value (analog signal) from the differential amplifier circuit 241 into a digital signal and supplies it to the control unit 243.

[0049] The control unit 243 controls the displacement amount of the probe 17 in the Z direction based on the load value output from the load cell 19. As the control unit 243, a device having a CPU, ROM, RAM, EEPROM, input / output interface, etc. can be applied. The control unit 243 realizes the fine adjustment process in the Z direction by the CPU executing a processing program (for example, Z direction adjustment program, etc.) stored in the ROM.

[0050] The method of fine adjustment in the Z direction at the time of first contact of the probe 17 by the control unit 243 will be described in detail in the operation section. The control unit 243 has a function as a position derivation unit for deriving the initial setting position in the Z direction.

[0051] The motor control unit 244 performs drive control on the Z knob drive unit 18 under the control of the control unit 243. The control method of the motor control unit 244 will also be described in detail in the operation section.

[0052] As the Z knob drive unit 18, for example, a motor or the like can be applied, and it drives the Z knob 13 under the control of the motor control unit 244. By driving the Z knob 13 by the Z knob drive unit 18, the position of the probe 17 in the Z direction is moved.

[0053] (A-2) Operation of the Embodiment Next, the processing operation of the initial setting of the position of the probe 17 by the position adjustment unit 10 according to the embodiment will be described with reference to the drawings.

[0054] FIG. 3 is a flowchart showing the processing operation of the initial setting of the position of the probe 17 by the position adjustment unit 10 according to the embodiment. FIG. 4 is a relational diagram showing the relationship between the output value of the load cell 19 and the displacement amount of the probe 17 in the Z direction.

[0055] The semiconductor wafer as the object to be inspected is placed on the stage 21, and the operator operates the stage drive unit 22 to adjust the position of the stage 21 to an appropriate position.

[0056] The operator looks into the microscope 23 and recognizes the electrode pad of the device on the semiconductor wafer and the probe 17. Then, the operator operates the X knob 11 and the Y knob 12 to move the probe 17 in the two-dimensional direction of the XY plane, and aligns the tip position of the probe 17 to be approximately at the center of the electrode pad (S101).

[0057] When the alignment of the probe 17 in the two-dimensional direction is completed, the operator operates the Z knob 13 to lower the probe 17 in the Z direction and bring the tip of the probe 17 close to the electrode pad (S102). Note that in the process of S102, in order to efficiently align the probe 17, it is assumed that the operator performs it manually, but it may also be performed automatically.

[0058] Next, for example, when the operator turns on a switch such as a setting start switch as a trigger, the initial setting process of the Z-direction position of the probe 17 starts.

[0059] A voltage of a predetermined value is applied to the load cell 19, and the load cell 19 can detect the load.

[0060] The control unit 243 instructs the motor control unit 244 to lower the probe 17 in the Z direction. In response to this, the motor control unit 244 drives the Z knob drive unit 18 to start lowering the probe 17 in the Z direction (S103).

[0061] At this time, for example, the motor control unit 244 lowers the probe 17 in the Z direction by 1 micron at a time. The control unit 243 compares the output voltage value of the load cell 19 that detects the contact load between the probe 17 and the electrode pad with a preset pressure dead zone threshold value (S104).

[0062] If the output voltage value is less than the pressure dead zone threshold value (S104 / YES), the process returns to S103, and the control unit 243 continues to instruct the motor control unit 244 to lower the probe 17 in the Z direction. On the other hand, if the output voltage value is greater than or equal to the pressure dead zone threshold value (S104 / NO), the process proceeds to S105.

[0063] Here, the pressure insensitive zone refers to the range in which the tip of the descending probe 17 can be regarded as having an unstable contact state with respect to the surface of the electrode pad. That is, it cannot be said that the probe 17 is in reliable contact with the electrode pad, and the pressure (reaction force) due to the contact load is also in an unstable state.

[0064] Therefore, using the pressure insensitive zone threshold value that can be regarded as having exited the pressure insensitive zone, when the output voltage value of the load cell 19 is less than the pressure insensitive zone threshold value, it is determined that the pressure (reaction force due to the contact load) is small and the contact state is unstable. Conversely, when the output voltage value of the load cell 19 is equal to or greater than the pressure insensitive zone threshold value, it is considered that the pressure is relatively large and the probe 17 is in reliable contact.

[0065] In S103 and S104, in order to exclude the unstable contact state, the probe 17 is gradually lowered, and the output voltage value of the load cell 19 is compared with the pressure insensitive zone threshold value to detect the state where the probe 17 is in reliable contact with the electrode pad.

[0066] Also, the operations of the motor control unit 244 and the Z knob drive unit 18 will be briefly described. For example, when the Z knob drive unit 18 is a stepping motor, the motor control unit 244 outputs a pulse signal proportional to the rotation angle of the Z knob drive unit 18 corresponding to the rotation amount of the Z knob 13 that descends by 1 micron at a time to the Z knob drive unit 18. Thereby, the probe 17 can be gradually lowered, for example, by 1 micron at a time.

[0067] In S105, when the output voltage value of the load cell 19 becomes equal to or greater than the pressure insensitive zone threshold value, the control unit 243 reads the displacement amount (z1 in FIG. 4) of the probe 17 lowered in the Z direction and the output value (f1 in FIG. 4) of the load cell 19, and stores (z1, f1) (S105).

[0068] Next, the control unit 243 further lowers the Z-direction position of the probe 17 by a predetermined descending displacement amount (for example, 50 μm, etc.) (S106). For example, after saving the value of the displacement amount z1 of the probe 17, the control unit 243 17 resets the displacement amount of the probe to zero. Then, the control unit 243 sets the value of the pre-set descending displacement amount, and the control unit 243 instructs the motor control unit 244 to lower the probe 17 by the descending displacement amount. The motor control unit 244 drives the Z knob drive unit 18 to lower the probe 17 by the descending displacement amount.

[0069] Then, the control unit 243 reads the displacement amount of the probe 17 lowered by the predetermined descending displacement amount (z2 in FIG. 4) and the output value of the load cell 19 at that time (f2 in FIG. 4), and saves (z2, f2) (S107).

[0070] Next, the control unit 243 substitutes (z1, f1) and (z2, f2) into Equation (1) to derive the initial setting value z0 in the Z direction of the probe 17 with respect to the electrode pad (S108). z0 = z1 - f1 / [(f2 - f1) / (z2 - z1)] …(1) Here, Equation (1) will be explained. In Equation (1), [(f2 - f1) / (z2 - z1)] indicates the change amount of the load per unit displacement amount in the Z direction. This utilizes the characteristic that in the case of a cantilever type probe, the relationship between the displacement amount in the Z direction and the reaction force (load change amount) is a proportional relationship, and obtains the load change amount per unit displacement amount in the Z direction.

[0071] In S106, the position of the probe 17 is lowered by the predetermined descending change amount. This is to obtain the relationship (proportional relationship) between the displacement amount in the Z direction and the reaction force (load change amount). Therefore, the value of the descending displacement amount for lowering the probe 17 can be any value.

[0072] In addition, for the relationship between the displacement amount in the Z direction and the reaction force (load change amount), it is necessary that the probe 17 is in stable contact with the electrode pad. Therefore, in order to exclude the unstable contact state of the probe 17, in S103 and S104, based on the output voltage value of the load converter 19 and a value equal to or higher than the pressure dead zone threshold value, it is determined whether the probe 17 is in stable contact.

[0073] When the initial setting value z0 of the probe 17 in the Z direction is derived, the control unit 243 gives an instruction to the motor control unit 244 to lower the probe 17 to the initial setting value in the Z direction. In response to this, the motor control unit 244 operates the Z knob drive unit 18, and by the Z knob drive unit 18 moving the Z knob 13, the probe 17 is lowered to the initial setting value z0 in the Z direction to perform initial alignment of the probe 17 position (S109).

[0074] As described above, the operator operates the X knob 11 and the Y knob 12 to finely adjust the position of the probe 17 on the XY plane. Thereafter, for the position of the probe 17 in the Z direction, the probe 17 automatically descends to the initial setting position derived by the control unit 243. Thereby, the initial setting position in the Z direction, which is the first contact of the probe 17 can be adjusted accurately 。

[0075] (A-3) Effects of the Embodiment As described above, according to this embodiment, by automating the alignment of the probe that depended on the individual operator's sense, the initial alignment of the probe can be adjusted with high accuracy.

[0076] In addition, according to this embodiment, even when the stage (chuck) on which the semiconductor wafer is placed is tilted when it moves, the alignment of the probe can be automatically performed, so that stable contact with the same accuracy can be obtained anywhere.

[0077] Furthermore, according to this embodiment, since the relationship between the displacement amount in the Z direction and the reaction force (load change amount) can be obtained, an operator can automatically perform contact at an arbitrary pressure or contact at an arbitrary probe overdrive amount.

[0078] (B) Other Embodiments Although various modified embodiments have been mentioned in the above-described embodiment, the present invention can also be applied to the following modified embodiments.

[0079] (B-1) The relationship between the displacement amount in the Z direction and the reaction force (load change amount) can be derived if at least two arbitrary points of the Z direction position and the load (reaction force) value are known. Therefore, after the stable contact between the probe 17 and the electrode pad, as long as at least two points of the Z direction position and the load (reaction force) value can be obtained, it is not limited to the method of the above-described embodiment.

[0080] For example, in the above-described embodiment, the case where the predetermined downward displacement amount is 50 μm is illustrated, but the value of the downward displacement amount is not limited to 50 μm, and any value can be used as long as the relationship between the displacement amount in the Z direction and the reaction force (load change amount) can be obtained. At this time, when the probe 17 is lowered, the electrode pad and / or the probe 17 may be damaged. Therefore, it is desirable to determine the value of the downward displacement amount in consideration of these points.

[0081] Also, for example, in the above-described embodiment, the second point is illustrated as the case where the control unit 243 obtains the Z direction position z2 where the probe 17 is lowered by the downward displacement amount and the load value f2 at that time, but it is not limited to this. For example, the control unit may lower the probe 17 until the output value from the load converter 19 becomes a predetermined load value, and obtain the Z direction position when the output value becomes the previous load value. Also in this case, since the second point can be obtained, the same effect as the above-described embodiment can be obtained.

[0082] If there are at least two points or more, the relationship between the displacement amount in the Z direction and the reaction force (load change amount) can be obtained. However, the relationship between the Z direction position and the load (reaction force) value may be three points or more.

[0083] (B-2) The inspection device described above 1 The position adjustment method in may be to perform the process illustrated in FIG. 3 every time the electrical characteristics of the device are inspected, or if the relationship between the displacement amount in the Z direction and the reaction force (load change amount) obtained in FIG. 3 can be used, it is not necessary to perform the process of FIG. 3 every time of inspection.

[0084] In other words, for each inspection target chip, the load change value per unit length (the slope of the proportional relationship between the Z direction displacement amount and the load change value) may be obtained by the process of FIG. 3, or if the already obtained load change value per unit length can be used, the load change value per unit length may be used to finely adjust the Z direction position of the probe 17

[0085] For example, after the initial setting of the probe position by the process of FIG. 3, when a displacement occurs to the inspection target chip or when the types of inspection target chips are different, etc., it is better to perform the process of obtaining the slope for each inspection target chip. On the other hand, for example, when the same type of chip is used as the inspection target, since the slope can be used as it is, in that case, the Z direction position of the probe 17

[0086] (B-3) Equation (1) derives the load change amount per unit length from (z1, f1) and (z2, f2), and the proportional formula of the load change amount per unit length is an equation for deriving the value of Z when passing through the point (z1, f1) and F = 0.

[0087] Equation (1) is an example and is not limited to this equation. It may also be an equation for deriving the value of Z when passing through the point (z2, f2) and F = 0.

Explanation of symbols

[0088] ​​1…Inspection device, 10…Position adjustment unit, 11…X knob, 12…Y knob, 13…Z knob, 14…Arm support part, 15…Isolator, 16…L arm part, 17…Probe, 18…Z knob drive part, 19…Load cell, 20…Housing, 21…Stage, 22…Stage drive part, 23…Microscope, 25…Plate member, 26…Upper part, 27…Lower part, 80…Electrode pad, 100…Main body part, 191…Strain gauge, 192…Strain gauge, 193…Strain gauge, 194…Strain gauge, 241…Differential amplifier circuit, 242…A / D converter, 243…Control unit, 244…Motor control unit, 251…Opening.

Claims

1. In an inspection apparatus for inspecting the electrical characteristics of a subject by using a contact that is electrically contacted to an electrode of the subject, a position adjustment unit having the contact, a position adjustment unit that adjusts the tip position of the contact, and a load detection unit that detects a contact load value between the contact and the electrode; a position derivation unit that derives an initial position indicating a physical initial contact position of the contact with the electrode based on a proportional relationship between a contact displacement amount indicating a movement amount of the contact in a specific direction and a contact load value of the contact and the electrode; a movement execution unit that moves the tip position of the contact to the initial position based on the initial position in a specific direction derived by the position derivation unit, and causes physical initial contact of the contact with the electrode is provided, wherein the position derivation unit measures a measurement result of the contact load value and the contact displacement amount when the contact load value becomes equal to or greater than a threshold value, and then measures a measurement result of the contact load value and the contact displacement amount when the contact displacement amount of the contact is slightly changed, derives the initial position by using a load change value per unit length derived by using the two measurement results and the measurement results An inspection apparatus characterized by the above.

2. The inspection apparatus according to claim 1, wherein the threshold value is a value at which the tip of the contact is in an unstable contact state with the surface of the electrode.

3. In a position adjustment unit that adjusts the tip position of a contact that is electrically contacted to an electrode of a subject, a position adjustment unit that adjusts the tip position of the contact; a load detection unit that detects a contact load value between the contact and the electrode; a position derivation unit that derives an initial position indicating a physical initial contact position of the contact with the electrode based on a proportional relationship between a contact displacement amount indicating a movement amount of the contact in a specific direction and a contact load value of the contact and the electrode; a movement execution unit that moves the tip position of the contact to the initial position based on the initial position in a specific direction derived by the position derivation unit, and causes physical initial contact of the contact with the electrode is provided, wherein the position derivation unit measures a measurement result of the contact load value and the contact displacement amount when the contact load value becomes equal to or greater than a threshold value, and then measures a measurement result of the contact load value and the contact displacement amount when the contact displacement amount of the contact is slightly changed, The initial position is derived using the load change value per unit length derived using the two measurement results and the measurement results. A position adjustment unit characterized by:

4. A position adjustment method for adjusting the position of a tip of a contactor that is to be brought into electrical contact with an electrode, using a position adjustment unit having a contactor, a position adjustment section that adjusts the position of the tip of the contactor, and a load detection section that detects a contact load value between the contactor and an electrode of an object under test, comprising: a position deriving unit deriving an initial position indicating a position of initial physical contact of the contactor with the electrode based on a proportional relationship between a contact displacement amount indicating a movement amount of the contactor in a specific direction and a contact load value of the contactor and the electrode; a movement execution unit, based on the initial position in the specific direction derived by the position derivation unit, moves a tip position of the contactor to the initial position, and brings the contactor into physical initial contact with the electrode; The position derivation unit measuring a contact load value and a contact displacement amount when the contact load value becomes equal to or greater than a threshold value, and thereafter measuring the contact load value and the contact displacement amount when the contact displacement amount of the contact is slightly changed; The initial position is derived using the load change value per unit length derived using the two measurement results and the measurement results. A position adjustment method comprising:

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