Height measuring circuit for wafer scribing machine and wafer scribing machine

Abstract

The embodiment of the invention provides a height measurement circuit for a wafer scribing machine and the wafer scribing machine, the height measurement circuit comprises a height measurement line detection loop and a height measurement trigger loop, the height measurement line detection loop and the height measurement trigger loop are connected through a positive height measurement line and a negative height measurement line, and the height measurement trigger loop comprises a timer chip. A trigger pin of the timer chip is connected with the height measurement line detection loop through the adjusting resistor group, the positive height measurement line and the negative height measurement line, and a voltage pin of the timer chip is connected with the height measurement line detection loop through the negative height measurement line; the height measurement line detection loop comprises a detection line connected with the wafer scribing machine, the detection line is conducted when a main shaft of the wafer scribing machine is in a contact state with the workbench, and the adjusting resistor set is used for adjusting a voltage threshold value between the positive height measurement line and the negative height measurement line. The embodiment of the invention provides a height measurement circuit for a wafer scribing machine and the wafer scribing machine, which can improve the height measurement precision and judge whether a height measurement line is broken or not.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of wafer cutting equipment, and in particular to a height measurement circuit for a wafer dicing machine and a wafer dicing machine. Background Art

[0002] Wafer dicing machine is an important processing equipment in the field of semiconductor packaging processing technology. It includes a spindle and a worktable, and a cutting blade is installed on the spindle. In order to ensure the accuracy of the measurement results, it is necessary to detect the degree of wear of the blade online and adjust the height of the spindle relative to the worktable according to the amount of wear of the blade. Therefore, it is necessary to measure the height of the blade through a height measuring device and adjust the height of the blade in time to ensure that the relative position of the blade and the workpiece remains unchanged during processing as much as possible.

[0003] The current contact height measurement solution is implemented through a relay module, and the relay action response cannot be adjusted, and thus the height measurement response time accuracy cannot be adjusted. Summary of the invention

[0004] In view of this, an embodiment of the present application provides a height measurement circuit and a wafer dicing machine for a wafer dicing machine, which can improve the height measurement accuracy and determine whether the height measurement line is broken.

[0005] According to an embodiment of the present application, a height measurement circuit for a wafer dicing machine is provided, characterized in that the height measurement circuit includes a height measurement line detection circuit and a height measurement trigger circuit, the height measurement line detection circuit is connected to the height measurement trigger circuit through a positive height measurement line and a negative height measurement line, the height measurement trigger circuit includes a timer chip, a trigger pin of the timer chip is connected to the height measurement line detection circuit through an adjustment resistor group and through the positive height measurement line and the negative height measurement line, and a voltage pin of the timer chip is connected to the height measurement line detection circuit through the negative height measurement line; the detection end of the height measurement line detection circuit is respectively connected to the spindle and the workbench of the wafer dicing machine, and is turned on when the spindle and the workbench of the wafer dicing machine are in contact, and the height measurement line detection circuit outputs a trigger signal to the trigger pin through the positive height measurement line and the negative height measurement line; the timer chip outputs a height measurement signal in response to the trigger signal to drive the spindle lifting driver to record the position of the spindle, and the adjustment resistor group is used to adjust the voltage threshold between the positive height measurement line and the negative height measurement line to adjust the trigger accuracy.

[0006] Optionally, the height measurement line detection circuit includes: a worktable detection circuit, one end of which is connected to the positive height measurement line and is connected to the negative height measurement line through a first relay, and the other end is connected to the worktable as a detection end; a spindle detection circuit, one end of which is connected to the negative height measurement line and is connected to the positive height measurement line through a second relay, and the other end is connected to the spindle as a detection end.

[0007] Optionally, the control end of the first relay is used to access a spindle detection signal, and the control end of the second relay is used to access a workbench detection signal.

[0008] Optionally, the workbench detection circuit includes a first workbench detection terminal and a second workbench detection terminal connected to the workbench; when the workbench detection signal is enabled, the normally closed contact of the first relay is disconnected, and the normally open contact of the first relay is closed, the first workbench detection terminal of the workbench detection circuit is connected to the positive height measurement line, and the second workbench detection terminal of the workbench detection circuit is connected to the negative height measurement line through the first relay, and the voltage between the positive height measurement line and the negative height measurement line is reduced.

[0009] Optionally, the spindle detection circuit includes a first spindle detection end and a second spindle detection end connected to the spindle; when the spindle detection signal is enabled, the normally closed contact of the second relay is disconnected, and the normally open contact of the second relay is closed, the first spindle detection end of the spindle detection circuit is connected to the negative height measurement line, and the second spindle detection end of the spindle detection circuit is connected to the positive height measurement line through the second relay, the voltage between the positive height measurement line and the negative height measurement line is reduced, and the height measurement trigger circuit sends the height measurement signal.

[0010] Optionally, the height measurement circuit also includes a sensor, a sensor output terminal of the sensor is connected to the positive height measurement line, and a sensor ground terminal of the sensor is connected to the negative height measurement line. When the spindle blocks the sensor signal, when the voltage between the sensor output terminal and the sensor ground terminal drops to less than the voltage threshold, the height measurement trigger circuit sends out the height measurement signal.

[0011] Optionally, the height measurement trigger circuit also includes a power converter and a power amplifier. A power converter is provided between the timer chip and the power amplifier. When the voltage between the trigger pin and the voltage pin of the timer chip is lower than the voltage threshold, the timer chip sends a 12VDC high level, the power converter converts the 12VDC high level into a 24VDC high level, and the power amplifier amplifies and outputs the height measurement signal.

[0012] Optionally, when the spindle is in contact with the workbench and the spindle does not block the sensor, the voltage difference between the positive altimeter line and the negative altimeter line is a high voltage; when the height of the spindle is lowered or the sensor is blocked, the voltage difference between the positive altimeter line and the negative altimeter line decreases, and the voltage between the trigger pin and the voltage pin is lower than the voltage threshold, the timer chip sends the altimeter signal.

[0013] Optionally, the adjustment resistor group includes an adjustable resistor, a first fixed resistor and a second fixed resistor, the adjustable resistor and the first fixed resistor are connected in parallel to the trigger pin, and the adjustable resistor and the first fixed resistor are connected in parallel and then connected in series to the power supply pin.

[0014] According to the height measurement circuit for a wafer dicing machine provided by the first embodiment of the present application, a height measurement line detection circuit is added to detect whether the height measurement line is broken. A timer chip with an adjustable resistor group is provided to adjust the voltage threshold between the positive height measurement line and the negative height measurement line, thereby adjusting the response of the height measurement model output by the timer chip, thereby adjusting the triggering accuracy of the entire height measurement circuit; and the height measurement circuit has high overall stability and good safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0016] Figure 1 A schematic structural diagram of a wafer dicing machine according to an embodiment of the first aspect of the present application;

[0017] Figure 2 A simplified structural diagram of a height measurement circuit for a wafer dicing machine according to an embodiment of the first aspect of the present application;

[0018] Figure 3 A circuit diagram of a height measurement line detection circuit for a height measurement circuit of a wafer dicing machine according to an embodiment of the first aspect of the present application;

[0019] Figure 4 A circuit diagram of a height measurement line detection circuit for measuring according to an embodiment of the first aspect of the present application;

[0020] Figure 5 A schematic circuit diagram of the conduction of the workbench height measurement line detection according to the height measurement line detection of the first aspect of the present application;

[0021] Figure 6 A schematic circuit diagram of the conduction of the spindle height line detection according to the height line detection of the first aspect of the present application;

[0022] Figure 7 It is a circuit diagram of a height measurement trigger circuit for a height measurement circuit of a wafer dicing machine according to an embodiment of the first aspect of the present application.

[0023] Description of reference numerals:

[0024] Wafer dicing machine 100;

[0025] Spindle 10; worktable 20. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the embodiments of the present application should fall within the scope of protection of the embodiments of the present application.

[0027] As mentioned above, the wafer dicing machine 100 is an important processing equipment in the field of semiconductor packaging processing technology, which includes a spindle 10 and a worktable 20, and a blade for cutting is provided on the spindle 10. In order to ensure the accuracy of the measurement results, it is necessary to perform online detection of the degree of wear of the blade, and adjust the height of the spindle relative to the worktable 20 according to the amount of wear of the blade. Therefore, it is necessary to measure the height of the blade through a height measuring device, and adjust the height of the blade in time to ensure that the relative position of the blade and the workpiece remains unchanged during processing as much as possible.

[0028] At present, there are two methods for height measurement: contact height measurement (CS) and non-contact height measurement (NCS). In the contact height measurement (CS) method, when the spindle 10 descends, the moment the spindle 10 contacts the workbench 20, the height measurement relay is turned on and sends a signal to record the position of the spindle 10, and then the spindle 10 rises rapidly. In the non-contact height measurement (NCS) method, when the spindle 10 descends, the spindle 10 blocks the light of the photoelectric switch, and the photoelectric switch sends a trigger signal to record the position of the spindle 10, and then the spindle 10 rises rapidly.

[0029] However, the current contact height measurement solution is implemented through a relay module, which has a complicated circuit, many fault points, and poor stability. At the same time, the relay action response cannot be adjusted, and thus the accuracy of the height measurement response time cannot be adjusted. The non-contact height measurement solution has a low accuracy.

[0030] In view of this, the present application proposes a height measurement circuit for a wafer dicing machine 100 and the wafer dicing machine 100 .

[0031] The following is attached to the instruction manual Figure 1-Figure 7 The height measurement circuit for wafer dicing 100 according to an embodiment of the present application is described in detail.

[0032] like Figure 1The figure shows a wafer dicing machine 100, whose main shaft 10 has two opposing blades that can move synchronously with the movement of the main shaft 10. Specifically, the two opposing blades are at the same horizontal height, and the two blades are located on the same axis. The two blades are arranged opposite to each other, and there is a gap between the two blades. In this article, the movement of one of the blades and the height measurement circuit between the blade and the workbench are used for description. The cooperation between the other blade and the workbench and the operation mode of the height measurement circuit are similar, and will not be described in detail.

[0033] The detection ends of the height measurement line detection circuit in the height measurement circuit are respectively connected to the spindle and the worktable of the wafer dicing machine, and are turned on when the spindle and the worktable of the wafer dicing machine are in contact, and the spindle position is recorded in response to the conduction condition for height measurement.

[0034] Specifically, when the height of the spindle 10 is reduced, the height of the blade of the spindle 10 is reduced at the same time. When the blade contacts the workbench, a loop is formed between the blade of the spindle 10 and the workbench 20, so that the detection ends connected to the spindle 10 and the blade are respectively turned on. The specific principle of height measurement can be found in the subsequent description of the height measurement circuit, which will not be repeated here.

[0035] It should be noted that if Figure 1-Figure 7 As shown, the spindle detection circuit of one of the blades includes a first spindle detection terminal SP11 and a second spindle detection terminal SP12. Similarly, the spindle detection circuit of the other blade also includes two spindle detection terminals, which are named as the third spindle detection terminal SP21 and the fourth spindle detection terminal SP22 for the convenience of distinguishing them from the first spindle detection terminal and the second spindle detection terminal. Similarly, the workbench detection circuit also includes a first workbench detection terminal CT1 and a second workbench detection terminal CT2. The two blades share a workbench and a workbench detection circuit.

[0036] like Figure 2 As shown, a height measurement circuit for a wafer dicing machine includes a height measurement line detection circuit and a height measurement trigger circuit. In some embodiments of the present invention, the height measurement detection circuit and the height measurement trigger circuit can be set as follows: Figure 2 The height measurement circuit board is shown in FIG. The height measurement line detection circuit is connected to the height measurement trigger circuit through the positive height measurement line and the negative height measurement line. The positive height measurement line and the negative height measurement line can be coupled to different voltage terminals, for example, the positive height measurement line can be coupled to a positive voltage source, and the negative height measurement line can be coupled to a ground terminal, so as to ensure that the voltage difference between the positive height measurement line and the negative height measurement line is greater than the voltage threshold when the blade and the spindle are not in contact.

[0037] The height detection circuit is described below.

[0038] If contact occurs between the blade of the spindle and the workbench, the detection end of the height measuring line detection circuit will be turned on, so that the voltage between the positive height measuring line and the negative height measuring line of the height measuring line detection circuit will drop to the threshold value, that is, the height measuring line detection circuit outputs a trigger signal to the trigger pin through the positive height measuring line and the negative height measuring line.

[0039] Specifically, see Figure 3 and Figure 4 , the spindle is lowered when measuring height. When the spindle is not in contact with the table, refer to Figure 3 , the positive high-sensing line CS+ and the negative high-sensing line CS- are disconnected.

[0040] After the spindle contacts the table, see Figure 4 , SP11, SP12, CT1, CT2 are turned on, then CS+ and CS- are turned on, and the circuit after conduction is as follows Figure 4 As shown by the dotted line in the figure, the voltage difference between CS+ and CS- will decrease and approach zero, and the height detection circuit will be activated and send out a trigger signal. Figure 3 and Figure 4 This is only an example, and other circuit structures may also be set, all within the scope of protection of this application. For example, CT1 connected to the workbench and SP11 connected to the spindle may be set, CT1 is coupled to CS+, and SP11 is coupled to CS-; when the spindle contacts the workbench, CT1 and SP11 are turned on, then CS+ and CS- are turned on, the voltage between CS+ and CS- will decrease and approach zero, the height measurement line detection circuit will be activated, and a trigger signal will be issued.

[0041] Alternatively, if Figure 3 As shown, the height measurement line detection circuit includes a worktable detection circuit and a spindle detection circuit. If one of the height measurement lines inside the spindle or the worktable is disconnected, the spindle blade cannot form a closed loop when in contact with the worktable, resulting in the voltage between the positive height measurement line and the negative height measurement line being unable to change. Even if the spindle is in contact with the worktable, the height measurement detection circuit does not output a detection signal, causing the spindle to continue to descend and damage the equipment. The worktable detection circuit and the spindle detection circuit in the height measurement line detection circuit can respectively detect whether the detection lines in the spindle and the worktable are disconnected to ensure the reliability of the height measurement circuit.

[0042] Specifically, one end of the workbench detection circuit is connected to the positive height measurement line CS+, and is connected to the negative height measurement line CS- through the first relay, and the other end is connected to the workbench as a detection end. One end of the spindle detection circuit is connected to the negative height measurement line CS-, and is connected to the positive height measurement line CS+ through the second relay, and the other end is connected to the spindle as a detection end. Figure 3 As shown in K1 in the figure, the second relay is Figure 3 As shown in K2.

[0043] like Figure 5 As shown in the figure, when the workbench detection signal (i.e., CT detection signal) is enabled, it indicates that the workbench height measurement line detection function is enabled. When the CT detection signal is enabled, the first relay K1 is energized, the normally closed contact of the first relay K1 is disconnected, the normally open contact is closed, CT2 is connected to CS-, and the circuit after the connection is as follows: Figure 5 As shown by the dotted line in . Since CT1 and CT2 are both connected to the contact surface of the workbench, that is, CT1 and CT2 are turned on at the workbench side, the normally closed contact of the K1 relay is disconnected, and the normally open contact is closed, so that CT1 is turned on with CS+, and CT2 is turned on with CS-, which is equivalent to connecting a resistor between CT+ and CS-, so that the voltage between CS+ and CS- will decrease and approach zero, and the height measurement line detection circuit will be activated and the trigger signal will be output.

[0044] When the spindle detection line is detected to see if it is disconnected, the spindle detection signal (i.e., SP detection signal) is enabled, and the circuit after conduction is as follows: Figure 6 As shown by the dotted line in, it is consistent with the action principle of CT detection signal use and will not be repeated here.

[0045] It should be noted here that the instruction manual is attached Figure 3-Figure 6 For the convenience of explanation and representation, the control end and the contact part of the first relay K1 are represented separately, and similarly, the control end and the contact part of the second relay K2 are represented separately. Those skilled in the art can understand that in actual relays, the control end and the contact part are an integrated structure and belong to the structure of the same relay. That is, the first relay K1 has an integrated control end and a contact part. The second relay K2 has an integrated control end and a contact part.

[0046] When the blade of the spindle contacts the workbench, the detection end of the height measurement line detection circuit is turned on, so that the voltage between the positive height measurement line and the negative height measurement line of the height measurement line detection circuit is reduced to the threshold value, that is, the height measurement line detection circuit outputs a trigger signal to the trigger pin of the height measurement trigger circuit through the positive height measurement line and the negative height measurement line; by connecting the spindle detection signal and the workbench detection signal, the circuit conduction of the spindle blade contacting the workbench can be simulated, so that the height measurement line detection circuit outputs a trigger signal to the trigger pin of the height measurement trigger circuit through the positive height measurement line and the negative height measurement line. Therefore, the height measurement line detection circuit can not only measure the spindle height, but also check whether there is an abnormality in the height measurement circuit, realizing a more comprehensive function and ensuring the reliability of the height measurement circuit.

[0047] Next, we will continue to explain the height measurement trigger circuit.

[0048] The timer chip in the height measurement trigger circuit will respond to the trigger signal and output a height measurement signal to drive the spindle lifting driver to record the spindle position and control the spindle to rise. Figure 3As shown in FIG. 1 , when the voltage between the positive height measuring line and the negative height measuring line does not change, it indicates that there is no contact between the spindle blade and the worktable. Therefore, the height measuring trigger circuit does not need to send a lifting signal to the spindle lifting drive.

[0049] Specifically, Figure 7 As shown, the high-measurement trigger circuit includes a timer chip, the voltage pin VCC of the timer chip is connected to the positive high-measurement line CS+ through an adjustment resistor group, and the voltage divider end of the adjustment resistor group is connected to the trigger pin of the timer chip (such as Figure 7 The positive high-sensing line CS+ is connected to the ground through capacitor c1, and the negative high-sensing line CS- is directly connected to the ground.

[0050] When the trigger signal is input to the height measurement trigger circuit, the voltage difference between the positive height measurement line CS+ and the negative height measurement line CS- becomes smaller, and the voltage value input to the trigger pin TRI G through the voltage divider end of the adjusting resistor group also becomes smaller. When the voltage difference between the positive height measurement line CS+ and the negative height measurement line CS- is less than the voltage threshold corresponding to the adjusting resistor group, the voltage value of the trigger pin TR IG meets the trigger condition, the timer chip starts working, and the output pin Q of the timer outputs a height measurement signal to drive the spindle lifting driver to record the position of the spindle.

[0051] The reset pin R of the timer chip is connected to the power pin VCC; the discharge terminal DIS, high trigger terminal THR and output terminal Q of the timer are connected to the power pin VCC through resistor R3 and grounded through capacitor C3; the control pin of the timer chip (such as Figure 7 ) is grounded through capacitor C2 to prevent interference.

[0052] The voltage threshold between the positive height measurement line and the negative height measurement line can be adjusted according to actual needs by adjusting the resistor group, so that the response accuracy of the height measurement trigger circuit can be adjusted to improve the height measurement accuracy. In addition, the change speed of the voltage value connected to the trigger pin TR IG can be adjusted by adjusting the capacitance value of the capacitor C1 and the resistance value of the adjustable resistor group, so as to adjust the response time of the height measurement circuit to adjust the response accuracy, that is, the response accuracy of the height measurement signal output by the timer chip can be adjusted to ensure the response at the moment when the spindle 10 contacts the workbench 20, so as to drive the spindle to lift and drive to record the position of the spindle 10 and increase the height of the spindle 10 to prevent the spindle 10 from continuing to fall and causing damage to the blade of the spindle 10. It can be understood that the timer chip included in the height measurement trigger circuit is connected to the height measurement line detection circuit through the adjusting resistor group, so by adjusting its own resistance value by adjusting the adjusting resistor group, the voltage value between the positive height measurement line and the negative height measurement line can be adjusted.

[0053] In other words, the voltage threshold between the positive height measurement line and the negative height measurement line can be adjusted, and the voltage change speed of the trigger pin TRI G can be adjusted, that is, the response accuracy of the height measurement trigger circuit can be adjusted to improve the height measurement accuracy.

[0054] Furthermore, the voltage threshold is 5-10 V, specifically 8 V. When the voltage difference between the positive height measurement line and the negative height measurement line is lower than the voltage threshold of 8 V, the height measurement trigger circuit sends a height measurement signal, triggers the spindle lifting driver to move and record the current position value.

[0055] Furthermore, the height measurement line detection circuit and the height measurement trigger circuit can be packaged into a circuit board to reduce failure points and increase stability.

[0056] like Figure 7 As shown, the adjustable resistor group includes an adjustable resistor, a first fixed resistor and a second fixed resistor. The adjustable resistor and the first fixed resistor are connected in parallel to the trigger pin. The adjustable resistor and the first fixed resistor are connected in parallel and then connected in series with the second fixed resistor to the power pin VCC. Figure 7 As shown in the resistor R0, the first fixed resistor is Figure 7 As shown in the resistor R, the second fixed resistor is Figure 7 As shown in the resistor R1.

[0057] Specifically, the regulating resistor group includes an adjustable resistor. Therefore, the overall resistance of the regulating resistor group can be adjusted by the adjustable resistor, so that the triggering voltage threshold of the timer chip can be adjusted to adjust the detection accuracy.

[0058] like Figure 7 As shown, the height measurement trigger circuit also includes a power converter (such as Figure 7 PS in the figure) and the power amplifier (as shown in Figure 7 ). A power converter is provided between the timer chip and the power amplifier. When the voltage between the trigger pin and the voltage pin of the timer chip is lower than the voltage threshold, the output terminal Q of the timer chip can output a 12VDC high level, and the power converter converts the 12VDC high level into a 24VDC high level. The power amplifier amplifies and outputs the high-measurement signal. Of course, the above voltages are only used as examples. Those skilled in the art can determine other voltage values ​​according to needs, which are all within the protection scope of this application.

[0059] Specifically, when the voltage between the trigger pin and the voltage pin of the timer chip of the height measurement trigger circuit is lower than the voltage threshold of 8VDC mentioned above, the Q pin of the timer chip sends out a 12VDC high level, which is converted into a 24VDC high level by the power converter, and the signal power is amplified by the power amplifier to output a height measurement signal, which triggers the spindle lifting driver to record the current height position value of the spindle. Among them, those skilled in the art can understand that DC is direct current.

[0060] like Figure 3 As shown, the height measurement circuit also includes a sensor, the sensor output terminal of the sensor is connected to the positive height measurement line, and the sensor ground terminal of the sensor is connected to the negative height measurement line. Figure 3 As shown by line NCS1+, the sensor ground terminal is Figure 3 As shown by line NCS1- in the figure. When the spindle blocks the sensor signal, the voltage between the sensor output terminal and the sensor ground terminal drops below the voltage threshold, and the height measurement trigger circuit sends a height measurement signal.

[0061] In addition, when the height of the spindle drops and blocks the sensor, the spindle's descent speed can be controlled to decrease, thereby ensuring that the spindle drives the blade to descend at a slower speed and contact the workbench, and ensuring that the blade rises quickly at the moment of contact with the workbench, thereby improving the accuracy of spindle height detection and response speed.

[0062] In some embodiments of the present invention, when the spindle is in contact with the workbench and the spindle does not block the sensor, the voltage between the positive height measurement line and the negative height measurement line is 5VDC. The voltage at this time is a 5V DC voltage. When the height of the spindle is reduced or the sensor is blocked, the voltage between the positive height measurement line and the negative height measurement line decreases, and the voltage between the trigger pin and the voltage pin is lower than the voltage threshold, the timer chip sends a height measurement signal.

[0063] In order to explain the test situation more clearly, the following Figure 4-6 The operation mode of the height measurement line detection circuit of the first aspect of the present application is described as follows:

[0064] like Figure 4 As shown in the figure, when the contact height measurement is adopted between the spindle and the worktable, the height of the spindle is lowered until the spindle contacts the worktable. When the spindle contacts the worktable, SP11 and SP12 are connected with CT1 and CT2, that is, the spindle detection circuit and the worktable detection circuit are connected, then CS+ and CS- are connected, the voltage between CS+ and CS- will decrease and approach zero, the height measurement signal triggers the circuit action, and sends out the height measurement signal to raise the spindle lifting drive.

[0065] When non-contact height measurement is used between the spindle and the worktable, the spindle height drops, shielding the NCS sensor, and the voltage between NCS1+ and NCS1- decreases. When the voltage between NCS1+ and NCS1- is lower than the voltage threshold, the height measurement signal triggers the circuit action, and sends a height measurement signal to raise the spindle lifting drive.

[0066] like Figure 5As shown in the figure, when the CT detection signal is enabled, it indicates that the workbench height measurement line detection function is enabled. At this time, the first relay, namely relay K1, is energized, the normally closed contact of relay K1 is disconnected, and the normally open contact of relay K1 is closed. Therefore, the second workbench detection terminal CT2 is connected to the negative height measurement line CS-. Both CT1 and CT2 are connected to the contact surface of the workbench, and CT1 and CT2 are connected on the workbench side. At this time, CT1 is connected to the positive height measurement line CS+, and CT2 is connected to CS-.

[0067] As a result, CS+ and CS- are turned on, and the voltage between CS+ and CS- will decrease and approach zero, thus being less than the voltage threshold. The high-measurement signal triggers the circuit to operate and sends out a high-measurement signal.

[0068] like Figure 6 As shown in the figure, when the SP detection signal is enabled, it means that the spindle height line detection function is enabled. The principle here is consistent with the action principle of the CT detection signal, so it will not be repeated.

[0069] The following is attached to the instruction manual Figure 7 The operation mode of the height measurement trigger circuit of the first aspect of the present application is described as follows:

[0070] The main control chip of the height measurement trigger circuit is the timer chip. When the voltage between the trigger pin and the voltage pin, that is, TRIG and Cvolt, is lower than 8VDC, the Q pin of the timer sends out a 12VDC high level, which is converted into a 24VDC high level through the PS power supply, and the signal power is amplified through the DTD power amplifier to output a height measurement signal. The height measurement signal triggers the spindle lifting driver to record the current position value.

[0071] When the spindle is not in contact with the workbench and the sensor is not blocked, the voltage between CS+ and CS- is 5VDC. When the spindle drops or the sensor is blocked, the voltage between CS+ and CS- decreases. When the voltage value is lower than the threshold (about 0.75VDC), the voltage between TRIG and Cvolt is lower than 8VDC, and the timer chip triggers the height measurement signal.

[0072] Among them, by adjusting the resistance value of the variable resistor R0, the CS+ and CS- trigger voltage thresholds can be changed, thereby adjusting the height measurement signal response time.

[0073] According to a second aspect of the present invention, a wafer dicing machine comprises a main shaft and a worktable, and the wafer dicing machine has the height measurement circuit for a wafer dicing machine of the first aspect.

[0074] A wafer dicing machine according to the second aspect of the present invention has the same beneficial effects as the height measurement circuit for wafer dicing machine of the first aspect because it has the height measurement circuit for wafer dicing machine of the first aspect. A height measurement line detection circuit is added to detect whether the height measurement line is broken. A timer chip with an adjustment resistor group is provided to adjust the voltage threshold between the positive height measurement line and the negative height measurement line, so as to adjust the response time of the height measurement model output by the timer chip. Adjust the accuracy of the height measurement response time. The overall stability of the height measurement circuit is high.

[0075] The above implementation methods are only used to illustrate the embodiments of the present application, and are not limitations on the embodiments of the present application. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the embodiments of the present application. Therefore, all equivalent technical solutions also belong to the scope of the embodiments of the present application. The scope of patent protection of the embodiments of the present application should be limited by the claims.

Claims

1. A height measurement circuit for a wafer dicing machine, characterized in that: The height measurement circuit includes a height measurement line detection circuit and a height measurement trigger circuit, the height measurement line detection circuit and the height measurement trigger circuit are connected through a positive height measurement line and a negative height measurement line, the height measurement trigger circuit includes a timer chip, a trigger pin of the timer chip is connected to the height measurement line detection circuit through an adjustment resistor group and through the positive height measurement line and the negative height measurement line, and a voltage pin of the timer chip is connected to the height measurement line detection circuit through the negative height measurement line; The detection ends of the height measurement line detection circuit are respectively connected to the spindle and the workbench of the wafer dicing machine, and are turned on when the spindle and the workbench of the wafer dicing machine are in contact. The height measurement line detection circuit outputs a trigger signal to the trigger pin through the positive height measurement line and the negative height measurement line; The timer chip outputs a height measurement signal in response to the trigger signal to drive the spindle lifting driver to record the position of the spindle, and the adjustment resistor group is used to adjust the voltage threshold between the positive height measurement line and the negative height measurement line to adjust the trigger accuracy.

2. The height measuring circuit according to claim 1, characterized in that: The height measurement line detection circuit comprises: A workbench detection circuit, one end of which is connected to the positive height measuring line and is connected to the negative height measuring line through a first relay, and the other end of which is connected to the workbench as a detection end; A spindle detection circuit, one end of which is connected to the negative height measurement line and to the positive height measurement line through a second relay, and the other end of which is connected to the spindle as a detection end.

3. The height measuring circuit according to claim 2, characterized in that: The control end of the first relay is used to access a spindle detection signal, and the control end of the second relay is used to access a workbench detection signal.

4. The height measuring circuit according to claim 3, characterized in that: The workbench detection circuit includes a first workbench detection end and a second workbench detection end connected to the workbench; When the workbench detection signal is enabled, the normally closed contact of the first relay is disconnected, the normally open contact of the first relay is closed, the first workbench detection end of the workbench detection circuit is connected with the positive height measurement line, and the second workbench detection end of the workbench detection circuit is connected with the negative height measurement line through the first relay, and the voltage between the positive height measurement line and the negative height measurement line is reduced.

5. The height measuring circuit according to claim 3, characterized in that: The spindle detection circuit includes a first spindle detection end and a second spindle detection end connected to the spindle; When the spindle detection signal is enabled, the normally closed contact of the second relay is disconnected, the normally open contact of the second relay is closed, the first spindle detection end of the spindle detection circuit is connected to the negative height measurement line, the second spindle detection end of the spindle detection circuit is connected to the positive height measurement line through the second relay, the voltage between the positive height measurement line and the negative height measurement line is reduced, and the height measurement trigger circuit sends the height measurement signal.

6. The height measuring circuit according to claim 1, characterized in that: The height measurement circuit also includes a sensor, a sensor output terminal of the sensor is connected to the positive height measurement line, and a sensor ground terminal of the sensor is connected to the negative height measurement line. When the main shaft blocks the sensor signal, when the voltage between the sensor output terminal and the sensor ground terminal drops to less than the voltage threshold, the height measurement trigger circuit sends out the height measurement signal.

7. The height measuring circuit according to claim 1, characterized in that: The height measurement trigger circuit also includes a power converter and a power amplifier. A power converter is provided between the timer chip and the power amplifier. When the voltage between the trigger pin and the voltage pin of the timer chip is lower than the voltage threshold, the timer chip sends a 12VDC high level, the power converter converts the 12VDC high level into a 24VDC high level, and the power amplifier amplifies and outputs the height measurement signal.

8. The height measuring circuit according to claim 6, characterized in that: When the spindle is in contact with the workbench and the spindle does not block the sensor, the voltage difference between the positive altimeter line and the negative altimeter line is a high voltage; When the height of the spindle decreases or the sensor is blocked, the voltage difference between the positive height measurement line and the negative height measurement line decreases, and the voltage between the trigger pin and the voltage pin is lower than the voltage threshold, the timer chip sends the height measurement signal.

9. The height measuring circuit according to claim 1, characterized in that: The regulating resistor group includes an adjustable resistor, a first fixed resistor and a second fixed resistor. The adjustable resistor and the first fixed resistor are connected in parallel to the trigger pin. After being connected in parallel to the first fixed resistor, the adjustable resistor and the second fixed resistor are connected in series to the power supply pin.

10. A wafer dicing machine, characterized in that: The wafer dicing machine comprises a main shaft and a worktable, and the wafer dicing machine has a height measurement circuit according to any one of claims 1 to 9.

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