TWI768733B - Wafer inspection method and wafer probing system - Google Patents

Abstract

A wafer inspection method and a wafer probing system are disclosed. In the wafer inspection method, a motorized chuck stage is controlled by a control rod to be displaced between an upper position and a lower position along Z-axis direction, to change a relative position of a wafer on the motorized chuck stage relative to a probe. The control rod is movable between an upper and a lower limit positions. The wafer inspection method includes: determining a position of the control rod based on a measurement signal; determining a first moving direction and a moving distance of the control rod based on a change of the measurement signal; generating a control signal based on the moving distance of the control rod; controlling the motorized chuck stage to be displaced along a second moving direction opposite to the first moving direction; and controlling an objective lens module to keep focusing on the wafer when the motorized chuck stage is on the move.

Description

Wafer inspection method and wafer inspection system

The present invention relates to a wafer inspection method and wafer inspection system.

Press, with the development of semiconductor technology, the application of integrated circuit (Integrated Circuit) has become more and more popular. In order to screen out defective products during or after the fabrication of the integrated circuit, the test signal must be transmitted to the integrated circuit through the test device. The integrated circuit is used to test whether it meets the expectations, so as to control the factory yield of the integrated circuit. Here, in the current testing technology, the probes of the probe device can directly contact the pads or I/O pads on the circuit to be tested (such as the wafer), and the probes of the probe device can be used to probe The probe sends a test signal to the circuit under test for testing, and then the probe sends the test result back to the testing device for analysis.

In the currently known testing devices, when the probe contacts the circuit to be tested for testing, the wafer is mounted on an electric chuck, and the electric chuck can rotate and move along the X, Y and Z directions to locate the wafer. The probe is fixed on the central position of the probe platform which can be lifted and displaced along an axial direction, and the probe platform is located above the electric chuck. In order to perform needle testing, the electric chuck and the camera are kept in the position aligned with the wafer, and the probe then contacts the pads from top to bottom relative to the circuit to be tested on the wafer to complete the detection.

In addition to the probe, the probe platform must also be equipped with other instruments required for testing. In the process of needle measurement, it is often necessary to fine-tune the height of the probe, and through some Move the probe up slightly to see if the probe marks are as expected or if the probe is actually touching the pad. However, it is very difficult to drive an extremely heavy probe platform for precise fine-tuning.

In view of this, the present invention provides a wafer inspection method and a wafer inspection system. In this method, a control rod controls an electric chuck to move along the Z-axis direction between an upper position and a lower position in an adjustment interval, so as to change the relative position of the wafer on the electric chuck relative to one of the probes. position, wherein the control rod can move between an upper limit position and a lower limit position within a displacement range. The wafer inspection method includes the following steps: judging the position of the control rod within the displacement interval according to a measurement signal; judging a first movement direction and a movement distance of the control rod according to the change of the measurement signal; The movement distance of the control rod generates a control signal; according to the control signal, the electric chuck is controlled to move in a second movement direction opposite to the first movement direction; and when the electric chuck moves, according to the control signal or The displacement of the electric chuck controls an objective lens module to maintain focus on the wafer.

The present invention also provides a wafer inspection system, which includes a casing, an electric chuck, a probe platform, a probe, a photography module, an objective lens module, a control rod, a sensor, a controller and a display screen. The electric chuck is arranged inside the casing and is used for carrying a wafer. The probe platform is arranged above the electric chuck, the probe is arranged on the probe platform and is fixed on the casing through the probe platform, and the needle tip of the probe is located in the casing. The camera module is used to capture the image of the wafer on the electric chuck. The objective lens module is optically coupled to the camera module and connected to the micro motor for maintaining focus on the wafer when the electric chuck moves. The control rod is arranged outside the casing and can move between an upper limit position and a lower limit position. The sensor signal is coupled to the joystick, when the position of the joystick changes When the sensor generates a control signal. The controller signal is coupled to the electric chuck, the camera module, the control rod, the micro motor and the sensor. The controller is used to control the electric chuck to move along a Z-axis direction according to the control signal, and to control the objective lens module to maintain focus on the wafer when the electric chuck moves. The display screen signal is coupled to the camera module, and the display screen includes a user interface for displaying the current image of the wafer when the electric chuck moves.

The present invention also provides another wafer inspection method. In this method, a second element controls a first element to be displaced between an upper position and a lower position in an adjustment interval along a Z-axis direction, so as to change a wafer relative to a position disposed on a probe stage. A relative position of a probe, wherein the second element can move between an upper limit position and a lower limit position within a displacement range. The wafer inspection method comprises the following steps: judging the position of the second element within the displacement interval according to a measurement signal; judging a first moving direction and a moving distance of the second element according to the change of the measurement signal; The movement distance of the second element generates a control signal; according to the control signal, the first element is controlled to be displaced along a second movement direction opposite to the first movement direction; and when the first element moves, according to the control signal or all The displacement of the first element controls an objective lens module to maintain focus on the wafer.

100: Wafer Inspection System

10: Chassis

20: Joystick

21: Chute

30: Electric chuck

40: Probe Platform

50: Probe

60: Display screen

62: Distance information

70: Photography Module

80: Controller

90: Objective lens module

91: The first drive unit

92: Second drive unit

W: Wafer

P: solder pad

Z: Z axis direction

Z1: up direction

Z2: Downward

D1: top position

D2: Bottom position

D: Adjustment interval

H1: upper limit position

H2: Lower limit position

H: displacement interval

S11~S14: Steps

FIG. 1 is a flowchart of an embodiment of a wafer inspection method of the present invention.

FIG. 2 is a schematic diagram of a wafer inspection system implementing the wafer inspection method.

FIG. 3 is a partial schematic diagram of an embodiment of a wafer inspection system for implementing the wafer inspection method.

FIG. 4 is another schematic diagram of a wafer inspection system implementing the wafer inspection method.

FIG. 5 shows an embodiment of the relative relationship between the variation of the measurement signal and the displacement distance of the electric chuck in the wafer inspection method of the present invention.

FIG. 6 illustrates another embodiment of the relative relationship between the variation of the measurement signal and the displacement distance of the electric chuck in the wafer inspection method of the present invention.

FIG. 7 illustrates another embodiment of the relative relationship between the variation of the measurement signal and the displacement distance of the electric chuck in the wafer inspection method of the present invention.

FIG. 8 illustrates yet another embodiment of the relative relationship between the variation of the measurement signal and the displacement distance of the electric chuck in the wafer inspection method of the present invention.

FIG. 9 is a schematic diagram of another embodiment of the wafer inspection method of the present invention.

10A to 10C illustrate how to display the virtual position information of the probe platform on the display screen according to the relative position of the probe platform with respect to the electric chuck.

FIG. 11 shows how the control lever is retracted into the casing when the lever is located at the upper limit position H1.

Please refer to FIG. 1 in conjunction with FIGS. 2 to 4 . FIG. 1 is a flow chart of steps of an embodiment of the wafer inspection method of the present invention, and FIGS. 2 to 4 are schematic diagrams of a wafer inspection system implementing the wafer inspection method.

The wafer inspection system 100 shown in FIGS. 2 to 4 is used to inspect the electrical condition of the wafer W. As shown in FIG. In one embodiment, the wafer inspection system 100 includes a casing 10 , a lever 20 , an electric chuck 30 , a probe platform 40 , a probe 50 , a display screen 60 , a camera module 70 , a controller 80 and a sensor .

The electric chuck 30 is disposed in the casing 10 so as to be displaceable along the Z-axis direction Z. And the electric chuck 30 is suitable for carrying the wafer W. The probe platform 40 is fixed on the casing 10 . The probe 50 is arranged on the electrical above the movable chuck 30. Specifically, the probe platform 40 is arranged above the electric chuck 30 , and the probe 50 is arranged on the probe platform 40 . The photographing module 70 is used for photographing the electric chuck 30 . Specifically, the camera module 70 is disposed on the casing and faces the wafer W on the electric chuck 30 to obtain an image of the wafer W during needle measurement, so as to observe the needle measurement status. The signal of the controller 80 is connected to the electric chuck 30 and the camera module 70 . The control rod 20 can be displaced between the upper limit position H1 and the lower limit position H2 , and the control rod 20 is electrically connected to the controller 80 . The sensor is connected to the control rod 20 and the controller 80 for signals. When the position of the control rod 20 changes, the sensor will generate a control signal. The controller 80 controls the electric chuck 30 and the camera module 70 along the Z axis according to the control signal. The axis direction Z displacement is the same distance.

The signal of the display screen 60 is connected to the camera module 70 . The display screen 60 includes a user interface, and the user interface can display the current position of the electric chuck 30 .

In one embodiment, the wafer inspection system 100 further includes a first driving unit 91 and a second driving unit 92, wherein the first driving unit 91 is connected to the electric chuck 30, the second driving unit 92 is connected to the camera module 70, and controls The controller 80 is connected to the first driving unit 91 , the second driving unit 92 and the control rod 20 for signals, but the present invention is not limited to this.

Here, the two ends facing the Z-axis direction Z are the upward direction Z1 and the downward direction Z2 respectively, and the probe platform 40 is located in the upper direction Z1 of the electric chuck 30 compared to the electric chuck 30 . In addition, the electric chuck 30 can be displaced along the Z-axis direction Z toward or away from the probe platform 40 , the wafer W on the electric chuck 30 contacts the tip of the probe 50 , and the tip of the probe 50 contacts the pad P of the wafer W And pierce the oxide layer to form electrical connections for detection. Here, the electric chuck 30 may perform two-stage Z-axis direction Z feed, and the feed amount along the Z-axis direction Z in the first stage is greater than the feed amount along the Z-axis direction Z in the second stage.

Specifically, the wafer inspection system 100 can set the displacement amount of the electric chuck 30 along the Z-axis direction Z in the first stage through the touch-sensitive display screen 60 . The electric chuck 30 can be set at a height at which the wafer W can be detected by contacting the probe 50 after the displacement in the first stage, which can be referred to as the setting of the detection height herein. The displacement of the electric chuck 30 along the Z-axis direction Z in the second stage is after setting the height at which the wafer W contacts the probe 50 for inspection, in order to check the needle mark of the probe 50 or check whether the needle tip of the probe 50 is not The fine-tuning distance required to accurately align the pads P of the wafer W.

In one embodiment, the displacement of the electric chuck 30 along the Z-axis direction Z is controlled by the control rod 20, and the control rod 20 can control the electric chuck 30 to be displaced between the upper position D1 and the lower position D2, wherein the upper position is The space between D1 and the lower position D2 is the adjustment section D. Here, the distance of the adjustment interval D must be greater than the needle overdrive (OD) for the probe 50 to penetrate the oxide layer. When the adjustment interval D is greater than the needle downstroke, it can ensure that the displacement of the electric chuck 30 can make the crystal The circle W does come off the tip of the probe 50 .

When the electric chuck 30 changes its position in the adjustment section D, the relative position of the wafer W located thereon with respect to the probe 50 can be changed at the same time. In this way, the needle tips of the probes 50 are separated from the wafer W, and the needle marks generated on the bonding pads P during the testing process can be observed or the position of the needle tips of the probes 50 can be adjusted.

Here, the control rod 20 is restricted to move in the displacement section H, and the displacement section H is extended along the Z-axis direction Z. Therefore, the displacement section H has an upper limit position H1 and a lower limit position H2 in the Z-axis direction Z, and the control rod 20 can be displaced between the upper limit position H1 and the lower limit position H2. That is, the space between the upper limit position H1 and the lower limit position H2 defines the displacement interval H. The control rod 20 can be displaceably arranged in the chute 21 extending along the Z-axis direction Z, the two ends of the chute 21 are respectively the upper limit position H1 and the lower limit position H2, and the chute 21 is located on the Z-axis. The length in the direction Z is the displacement interval H. Furthermore, in this embodiment, the displacement of the control rod 20 between the upper limit position H1 and the lower limit position H2 can correspondingly control the displacement of the electric chuck 30 between the upper position D1 and the lower position D2.

FIG. 1 is a flowchart of one embodiment of a method for wafer inspection using a wafer inspection system 100 . In this embodiment, when the detection is started, the position of the control rod 20 within the displacement interval H is first determined according to the measurement signal (step S11 ). After judging the position of the control rod 20 , the displacement amount for the subsequent control of the displacement of the electric chuck 30 is defined according to the moving distance of the control rod 20 when the control rod 20 is operated subsequently.

Here, the source of the measurement signal based on which the position of the control rod 20 is determined may be an analog signal or a digital signal. In one embodiment, in the method of determining the position of the control rod 20 through digital signals, a plurality of sensors can be set in the displacement interval H of the control rod 20, and each sensor is connected to the control rod 20 and the controller 80 by signals, respectively. Each sensor can respectively generate a measurement signal corresponding to the position of the control rod 20, and the controller 80 generates a control signal according to the measurement signal. The first driving unit 91 and the second driving unit 92 control the electric chuck 30 and the camera according to the control signal. Module 70 is displaced.

For example, when the displacement interval H of the control rod 20 is 10 cm, sensors can be arranged at positions of every 1 cm in the displacement interval H, and each sensor is correspondingly located in the displacement interval H of the control rod 20 At different positions within the control rod 20, when the control rod 20 is at different positions in the displacement interval H, the sensor at the position of the control rod 20 generates a digital measurement signal, and through the digital measurement signal, it can be determined that the control rod 20 is in The position within the displacement interval H. Of course, when the control rod 20 is displaced, the displacement distance of the control rod 20 can also be determined by changing the digital measurement signal. The aforementioned distance and number of sensors are only examples for convenience of description, and the present invention is not limited to Therefore, it can be adjusted according to different usage habits or needs. In one embodiment, the sensor may be a proximity switch.

In one embodiment, in the method of determining the position of the control rod 20 through an analog measurement signal, the control rod 20 may be connected to an electronic component that can generate an analog signal corresponding to the displacement of the control rod 20 . Specifically, the lever 20 is an electronic component that can be connected to a voltage change, a resistance change, a capacitance change, or an inductance change. When the control rod 20 is located at each position within the displacement interval H, a corresponding analog measurement signal value can be measured. In a specific embodiment, when the control rod 20 is connected to an electronic component that can generate voltage changes, each position of the control rod 20 in the displacement interval H can measure a corresponding different voltage value. In this way, the position of the control rod 20 within the displacement interval H can be determined by detecting the voltage value. Of course, when the control rod 20 is displaced, the movable distance of the control rod 20 can also be known by corresponding to the change of the voltage value. Here, since a general computer system can only read digital signals, in this embodiment, the measured analog signals can be further converted into digital signals for the computer system to read and judge.

Further, when the control rod 20 is operated to move, the first moving direction and the moving distance of the control rod 20 are determined according to the change of the measurement signal (step S12 ). In one embodiment, when it is determined that the position of the control rod 20 is at the lower limit position H2 of the displacement interval H, the moving distance of the control rod 20 moving toward the upper limit position H1 can be further determined here.

After determining that the control rod 20 is displaced from the lower limit position H2 toward the upper limit position H1 according to the change of the measurement signal, a control signal is generated according to the movement distance of the control rod 20 (step S13 ). Next, the electric chuck 30 and the photographing module 70 are controlled to be displaced by the same distance according to the control signal (step S14 ). In this embodiment, the controller 80 is used to generate a control signal, and the first driving unit 91 and the second driving unit 92 respectively drive the electric chuck according to the control signal 30 and the photographing module 70 are displaced by the same distance, and the distance between the electric chuck 30 and the photographing module 70 remains unchanged after the displacement of the electric chuck 30 and the photographing module 70 . In other embodiments, the electric chuck 30 and the photographing module 70 may be displaced synchronously or asynchronously, and the present invention is not limited thereto.

In this embodiment, the electric chuck 30 is controlled to move from the upper position D1 to the lower position D2 based on the control signal of the moving distance of the control rod 20 from the lower limit position H2 to the upper limit position H1. That is, the displacement direction of the control rod 20 is opposite to the direction in which the displacement of the electric chuck 30 is controlled.

More specifically, the relative relationship of adjusting the displacement amount of the electric chuck 30 according to the movable distance of the control rod 20 may also have different corresponding relationships, as shown in FIG. 5 to FIG. 8 . Here, the different correspondences for adjusting the displacement of the electric chuck 30 according to the movable distance of the control rod 20 may be software or programs written into the hardware.

Referring to FIG. 5 , in one embodiment, the proportion of the movable distance of the control rod 20 in the displacement interval H has a linear correlation with the proportion of the displacement distance of the electric chuck 30 in the adjustment interval D. As shown in FIG. 5 , when the control rod 20 is displaced so that the corresponding measurement signal changes, the displacement distance of the electric chuck 30 and the change of the measurement signal corresponding to the movement of the control rod 20 may have a 1:1 linear correlation. That is to say, when the operator adjusts the control rod 20 to the lower limit position H2, it can be intuitively regarded as the initial position of the electric chuck 30, and the adjustment of the position of the control rod 20 in the displacement interval H can directly correspond to the electric chuck 30. The position ratio of the chuck 30 in the adjustment section D is convenient for the operator to observe and operate. Of course, the corresponding relationship between the change of the measurement signal corresponding to the movement of the control rod 20 and the displacement distance of the electric chuck 30 is not limited to a 1:1 linear correlation, and can also be changed to 1:2, 2 depending on the environment or hardware requirements : 1 or other scale value.

In another embodiment, as shown in FIGS. 6 to 8 , the relative relationship between the change of the measurement signal corresponding to the movement of the control rod 20 and the displacement distance of the electric chuck 30 may also be nonlinear. Specifically, if the change of the measurement signal corresponding to the movement of the control rod 20 is taken as the horizontal axis, and the displacement distance of the corresponding electric chuck 30 is taken as the vertical axis, a curve can be drawn, thereby making the electric chuck 30 move. The analog signal changes corresponding to the displacement distance and the movement of the control rod 20 can be expected. Here, the relative relationship curve between the change of the measurement signal and the displacement distance of the electric chuck 30 can be adjusted as required.

In other embodiments, in addition to controlling the relationship between the change of the measurement signal and the displacement distance of the electric chuck 30 through software, the displacement range (such as the maximum displacement amount and the minimum displacement amount) of the electric chuck 30 can be further limited. This corresponds to different hardware requirements.

In one embodiment, a plurality of control nodes are included between the upper limit position H1 and the lower limit position H2 of the displacement interval H, and each control node will generate a different measurement signal value. When the signal value is the same as the measurement signal value corresponding to the control node, the control signal can be generated. The aforementioned control node may be a physical position sensor (outputting a digital signal) or a non-physical control node (analog signal value) that defines the position according to the moving distance signal.

In one embodiment, the control nodes may be evenly arranged in the displacement interval H. For example, the range of the displacement interval H is 10 cm, and when the control nodes are evenly arranged in the displacement interval H, the measurement signal value of every 1 cm interval in the displacement interval H matches the measurement signal corresponding to the control node, and the difference between the control nodes The distance (1 cm) is defined as the segmented activity distance. Here, the displacement interval H is divided into a segmented moving distance corresponding to the number of control nodes. Therefore, when it is determined that the moving distance of the control rod 20 is in line with the multiple of the segmented moving distance, a control signal can be generated, and the moving distance The proportion value occupied in the displacement section H is the same as the proportion value occupied by the displacement distance of the electric chuck 30 in the adjustment section D.

Here, if the range of the entire adjustment interval D of the electric chuck 30 is 100 μm (microns), then the adjustment lever 20 can be displaced by one segment movable distance to adjust the displacement of the electric chuck 30 by a distance of 10 μm. Accordingly, in addition to restricting the control rod 20 to control each displacement of the electric chuck 30 according to the set distance, each adjustment of the control rod 20 corresponds to the displacement distance of the control electric chuck 30 is defined in advance, and the operator can The number of times of adjusting the control rod 20 predicts the adjusted displacement distance of the electric chuck 30 , thereby improving the convenience in operation.

In addition, the distribution of the control nodes corresponding to the positions of the control rods 20 is not limited to the average distribution disclosed in the foregoing embodiments. In one embodiment, the control nodes in the displacement interval H are not evenly distributed, and the distribution density of control nodes in the interval closer to the lower limit position H2 is higher than the distribution density of control nodes in the interval closer to the upper limit position H1. In this way, when the position of the control rod 20 in the displacement interval H is closer to the lower limit position H2, it means that the position of the electric chuck 30 is closer to the probe 50. In this state, in order to avoid the transient feeding damage of the electric chuck 30 The probe 50, the closer to the lower limit position H2, the higher the distribution density of the control nodes, the shorter the distance that the control rod 20 generates the control signal due to the displacement, in addition to the more fine control of the displacement distance of the control rod 20, and accordingly Correspondingly, the position of the electric chuck 30 can be adjusted more precisely, and the damage of the probe 50 can be avoided.

It can be seen from the above embodiments of the distribution of different control nodes in the displacement interval H that by adjusting the control nodes, the distance the electric chuck 30 is displaced by each movement of the control rod 20 can be relatively changed. self-adjustment due to physical limitations.

Furthermore, based on the above, when the number of control nodes required in the displacement interval H is more, the structure of determining the position of the control rod 20 through the analog signal will be better than that through the digital method. The signal determines the structure of the position of the control rod 20 . Because the hardware structure for judging the position of the joystick 20 through digital signals must increase the number of sensors according to the number of control nodes, when the number of control nodes increases, the cost of the hardware structure for judging the position of the joystick 20 through digital signals The higher it is, and the hardware architecture that determines the position of the joystick 20 through an analog signal will not have the same problem.

In addition, in one embodiment, the displacement distance of the electric chuck 30 can be further continuously detected, and a synchronization signal is generated according to the displacement distance, and then the camera module 70 and the electric chuck 30 are controlled to displace synchronously according to the synchronization signal. In this way, the position of the electric chuck 30 is changed synchronously with the position of the photographing module 70 , so that the photographing module 70 can still maintain focus to obtain a clear image after the position of the electric chuck 30 is changed.

In this embodiment, the continuous detection of the displacement distance of the electric chuck 30 can be displayed on the display screen 60 synchronously, so that the operator can know the position and adjustment status of the electric chuck 30 at any time, so as to improve the convenience of operation, and Accordingly, the occurrence of operation errors can be reduced.

In some embodiments, the camera module 70 is fixed on the casing 10 of the wafer inspection system 100 and is kept in an immovable state. In order for the camera module 70 to capture a clear image of the wafer W carried on the electric chuck 30 , the wafer inspection system 100 includes an objective lens module 90 . As shown in FIGS. 10A to 10C , the objective lens module 90 is disposed between the photographing module 70 and the electric chuck 30 , and is optically coupled to the photographing module 70 . The objective lens module 90 is connected to a micro motor, and the signal of the micro motor is connected to the controller 80 . When the electric chuck 30 moves, the micro motor can drive the objective lens module 90 to maintain focus on the wafer W along the Z-axis direction according to the control command from the controller 80 . The controller 80 generates the control command according to the control signal generated by the sensor, and the sensor generates the control signal according to the displacement of the control rod 20 . In some embodiments, the objective lens module 90 is driven synchronously with the movement of the motorized chuck 30 .

In some embodiments, when the control rod 20 does not move and the objective lens module 90 remains in a stationary state, the operator can replace the objective lens module 90 with different magnifications.

In some embodiments, the display screen 60 may be a touch display screen, and the joystick 20 may not be a physical element but a virtual joystick displayed on the display screen 60 . The operator can move the virtual joystick between an upper limit position and a lower limit position displayed on the display screen 60 through touch control.

As shown in FIG. 9 and FIGS. 10A to 10C, when the lever 20 is positioned at the upper limit position H1, the electric chuck 30 is positioned at the lowest position. When the control lever 20 is positioned at the lower limit position H2, the electric chuck 30 is positioned at the highest position, and this position can be regarded as the origin position of the electric chuck 30 . When the control rod 20 is moved by the operator, the display screen 60 will continuously display the distance information of the electric chuck 30 , and the distance information refers to the distance that the electric chuck 30 has moved from the origin position. The distance information helps the operator realize whether the tip of the probe 50 is about to touch the wafer W on the motor chuck 30 .

In a wafer inspection system, the probe stage 40 is usually much heavier than the motorized chuck 30 , so higher power and stronger mechanism are required to drive the probe stage 40 to move than to drive the motorized chuck 30 . In the present invention, the moving direction of the control rod 20 is opposite to the moving direction of the electric chuck 30, so when the operator operates the control rod 20 to move from the upper limit position H1 to the lower limit position H2, it will feel as if he is controlling the probe. The needle platform 40 moves down without realizing that the motorized chuck 30 is actually being lifted up.

In some embodiments, as shown in FIG. 10C , when the control lever 20 is at the lower limit position H2 , the display screen 60 will not display the distance information 62 . In other words, the display screen 60 displays the distance information 62 only when the control rod 20 leaves the lower limit position H2. This is because when the joystick When the 20 is at the lower limit position H2, the electric chuck 30 is already at the highest position (origin position), and cannot move further upward. As mentioned above, the distance information 62 is displayed to help the operator realize whether the tip of the probe 50 is about to touch the wafer W on the electric chuck 30. When the electric chuck 30 is already at the highest position (origin position), Displaying distance information 62 at this time does not provide any assistance to the operator.

In some embodiments, the operator can only use the control lever 20 to control the electric chuck 30 to ascend to a specific position when the tip of the probe 50 has not yet contacted the wafer W. In other words, when the lever 20 is at the lower limit position H2, the surface of the wafer W is only close to the tip of the probe 50, but not in contact therewith. When the control lever 20 is at the lower limit position H2, the operator can precisely control the electric chuck 30 to rise to a higher position by other control means. For example, the operator can perform touch operations through a graphical user interface on the display screen 60 , thereby precisely controlling the electric chuck 30 to ascend until the surface of the wafer W contacts the tip of the probe 50 .

As shown in FIG. 11 , in some embodiments, when the control rod 20 is located at the upper limit position H1 , the control rod 20 can be partially or completely retracted into the casing 10 .

In some embodiments, the lever 20 is a physical component disposed on the housing 10 of the wafer inspection system 100 .

Although the present invention has been disclosed above by embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some modifications and changes without departing from the spirit and scope of the present invention. Therefore, as long as these modifications and changes are within the scope of the appended claims and their equivalents, the present invention will also cover these modifications and changes.

S11~S14: Steps

Claims (14)

A wafer detection method, which controls an electric chuck along a Z-axis direction to be displaced between an upper position and a lower position in an adjustment interval, so as to change a wafer on the electric chuck relative to a A relative position of the probe, the control rod can move between an upper limit position and a lower limit position within a displacement range, the wafer inspection method includes: judging that the control rod is within the displacement range according to a measurement signal according to the change of the measurement signal to determine a first movement direction and a movement distance of the control rod; generate a control signal according to the movement distance of the control rod; control the electric chuck according to the control signal One of the first moving directions is displaced in a second moving direction; and when the electric chuck moves, an objective lens module is controlled to maintain focus on the wafer according to the control signal or the displacement of the electric chuck, wherein the objective lens The module is arranged between a photographing module and the electric chuck and is optically coupled to the photographing module. The wafer inspection method of claim 1, wherein the lever is a virtual lever, and the virtual lever can move between an upper limit position and a lower limit position displayed on a touch display screen. The wafer inspection method according to claim 1, further comprising: displaying a current distance between a probe stage and the electric chuck on a display screen. The wafer inspection method according to claim 1, further comprising: detecting a current position of the control rod; and displaying a current position information of the electric chuck on a display screen. The wafer inspection method according to claim 1, wherein the movement of the objective lens module and the electric chuck is synchronized. The wafer inspection method as claimed in claim 1, wherein the probe is disposed on a probe platform, the probe and the probe platform are both static, and the wafer inspection method further comprises: according to a For the relative position, a displacement information of the electric chuck relative to its origin position is displayed on a display screen. A wafer inspection system, comprising: a casing; an electric chuck, disposed inside the casing and used to carry a wafer; a probe platform, disposed above the electric chuck; a probe, is arranged on the probe platform and fixed on the casing through the probe platform, wherein the needle tip of the probe is located in the casing; a camera module is used to capture the wafer located on the electric chuck the image; an objective lens module optically coupled to the camera module and connected to a micro motor, the objective lens module is used to maintain focus on the wafer when the electric chuck moves; a control rod is arranged on the machine The outside of the shell is movable between an upper limit position and a lower limit position; a sensor, the signal is coupled to the control rod, when the position of the control rod changes, the sensor generates a control signal; a control The signal is coupled to the electric chuck, the camera module, the control rod, the micro motor and the sensor, and the controller is used to control the electric chuck along a Z-axis according to the control signal moving in the direction, and controlling the objective lens module to maintain focus on the wafer when the electric chuck moves; and a display screen, the signal is coupled to the camera module, and the display screen includes a user interface, the user The interface is used to display a current image of the wafer when the electric chuck moves. A wafer inspection method, which controls a first element to be displaced between an upper position and a lower position in an adjustment area along a Z-axis direction via a second element, so as to change a wafer relative to a probe platform set A relative position of the upper probe, the second element can move between an upper limit position and a lower limit position within a displacement interval, the wafer inspection method includes: judging the second element according to a measurement signal the position within the displacement interval; determine a first movement direction and a movement distance of the second element according to the change of the measurement signal; generate a control signal according to the movement distance of the second element; control the control signal according to the control signal The first element is displaced along a second moving direction opposite to the first moving direction; and when the first element moves, an objective lens module is controlled to maintain focus on the first element according to the control signal or the displacement of the first element on the wafer, wherein the objective lens module is disposed between a camera module and the first element and is optically coupled to the camera module. The wafer inspection method according to claim 8, wherein the first element is an electric chuck. The wafer inspection method according to claim 8, wherein the second element is a virtual joystick, and the virtual joystick can move between an upper limit position and a lower limit position displayed on a touch display screen . The wafer inspection method according to claim 8, further comprising: displaying a current distance between the probe platform and the first element on a display screen. The wafer inspection method according to claim 8, further comprising: detecting a current position of the second element; and displaying a current distance information between the first element and the probe platform on a display screen. The wafer inspection method according to claim 8, wherein the movement of the objective lens module and the first element is synchronized. The wafer inspection method according to claim 8, wherein the probe and the probe platform are both static, and the wafer inspection method further comprises: displaying the second element on a display screen according to a relative position of the second element A distance information of the first element relative to its origin position.

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