Disclosure of Invention
The invention provides a precision laser processing wafer moving system.
The object of the invention is achieved in the following way: the precision laser processing wafer moving system comprises a rack, wherein a moving system for transferring a wafer tray from a wafer storage box on the rack to a wafer vacuum chuck of a cutting platform for laser processing is arranged on the rack, and the moving system comprises a linear transferring mechanism, a rotary transferring mechanism and a wafer vacuum chuck moving mechanism; a material supporting frame capable of storing a wafer tray is arranged at a transfer position below the linear transfer mechanism; the linear transfer mechanism converts the wafer tray between a clamping position and a transfer position of the wafer storage box; the transfer mechanism is rotated to enable the wafer tray to be switched between a transfer position and a processing transfer position on the cutting platform; the wafer vacuum chuck moving mechanism enables the wafer tray to move linearly on the cutting platform along the X direction and the Y direction.
The linear transfer mechanism comprises a wafer clamping mechanism and a clamping linear driving mechanism for driving the wafer clamping mechanism to move linearly; the moving part of the clamping linear driving mechanism comprises a linear transfer slide block; the linear transfer sliding block is provided with a clamping sliding block, and the clamping sliding block can move along the moving direction of the linear transfer sliding block; a clamping slide block return spring is arranged between the clamping slide block and the linear transfer slide block; the length of the clamping slide block return spring is along the moving direction of the clamping slide block.
A clamping slide block displacement detection mechanism is arranged between the clamping slide block and the linear transfer slide block; namely, a slide block displacement sensor is arranged on the linear transfer slide block, and slide block displacement detection strips are arranged at corresponding positions on the clamping slide block; or a slide block displacement sensor is arranged on the clamping slide block, and a slide block displacement detection strip is arranged at a corresponding position on the linear rotating slide block.
The wafer clamping mechanism comprises a clamping connecting plate, the upper end of the clamping connecting plate is fixedly connected with a clamping slide block, and the lower end of the clamping connecting plate is connected with an upper clamping plate and a clamping cylinder body; wherein the piston head of the clamping cylinder is connected with the lower clamping plate; the front end part of the upper clamping plate is provided with a downward clamping baffle, and the corresponding position of the lower clamping plate is provided with a baffle avoiding groove; the lower end of the clamping separation blade extends into the separation blade avoiding groove.
A clamping plate spring is arranged between the upper clamping plate and the lower clamping plate; when the upper clamping plate and the lower clamping plate are in a hollow state, the lower clamping plate is pulled back to be in contact with the upper clamping plate by the clamping plate spring; the upper clamping plate is provided with a clamping plate displacement sensor, and the lower clamping plate is provided with a clamping plate displacement detection strip matched with the lower clamping plate.
The material supporting frame comprises a material supporting bottom plate, two parallel material supporting guide rails are arranged on the material supporting bottom plate, and the material supporting guide rails are driven by a guide rail driving mechanism to move relatively or oppositely along the material supporting bottom plate; the guide rail driving mechanism is a synchronous belt conveying mechanism arranged on the material supporting bottom plate, a synchronous belt connecting plate and two synchronous belt connecting plates are respectively fixed on synchronous belts on two sides of the synchronous belt conveying mechanism and move oppositely or oppositely, and each synchronous belt connecting plate is connected with one material supporting guide rail.
The material supporting bottom plate is provided with at least one material supporting bottom plate displacement sensor, and the synchronous belt connecting plate is provided with a connecting plate displacement detection strip corresponding to the material supporting bottom plate displacement sensor; and a proximity switch is arranged on the material supporting guide rail.
The rotary transfer mechanism comprises a transfer connector which is rotatably arranged on the frame, transfer lifting cylinders are respectively arranged at two ends of the transfer connector, transfer lifting cylinder guide rails are arranged on the outer side surfaces of the transfer lifting cylinders, a transfer cylinder connecting plate is fixed to a piston head of each transfer lifting cylinder, and a transfer lifting cylinder sliding block is fixed to the transfer cylinder connecting plate; the transfer lifting cylinder sliding block and the transfer lifting cylinder guide rail form a guide rail pair; the outer side of the transfer lifting cylinder slide block extends out of a cantilever, and a transfer sucker is fixed on the cantilever.
A transfer displacement detection strip is arranged on the transfer connector; two transfer displacement sensors are arranged on the rack along the rotation track of the transfer displacement detection strip; when the transfer displacement detection strip moves from one transfer displacement sensor to the other transfer displacement sensor, one transfer sucker moves from the transfer displacement to the processing transfer position, and the other transfer sucker moves from the processing transfer position to the transfer position; set up annular transportation spacing groove around the axis of transporting motor output shaft in the frame, set up the lower extreme in the transportation spacing groove and transport the spacing post of transportation of spacing groove fixed, the upper end is passed to the transportation connector, and the angle assurance of transportation spacing groove is transported the spacing post and is rotated 180 degrees.
The wafer vacuum chuck moving mechanism comprises a rack, wherein an X sliding seat moving along the X direction is arranged on the rack; an XY sliding seat moving along the Y direction is arranged on the X sliding seat; a rotating seat is arranged on the XY sliding seat; the rotary base is provided with a wafer vacuum chuck.
The invention has the beneficial effects that: and arranging a slide block displacement sensor to detect whether the wafer tray is in place in the front-back direction or not. After the wafer tray is detected to be in place, the clamping cylinder starts to act to clamp, and the clamping plate displacement sensor detects whether the upper position and the lower position of the lower clamping plate are in place or not and whether the wafer tray 4 is clamped together with the upper clamping plate or not. Thereby accurately clamping the wafer tray. The spacing between the material supporting guide rails is adjustable, and the material supporting guide rails can meet the storage requirements of wafer trays with different specifications. The two rotating structures of the transfer suckers can enable the processed wafer tray to return to the transfer position and finally return to the wafer storage box, and the working procedures are saved.
Detailed Description
The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. In the present invention, unless otherwise explicitly specified or limited, the terms "connected," "fixed," "disposed," and the like are to be construed broadly, as meaning either fixedly connected, detachably connected, or integrally formed; may be directly connected or indirectly connected through an intermediate, unless otherwise specifically limited. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
Unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features, or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
As shown in fig. 1-13, a precision laser processing wafer moving system includes a frame 1, and a moving system for transferring a wafer tray 4 from a wafer magazine 2 on the frame 1 to a wafer vacuum chuck 75 of a cutting platform 7 for laser processing is disposed on the frame 1. The moving system comprises a linear transfer mechanism, a rotary transfer mechanism 6 and a wafer vacuum chuck moving mechanism. The transfer position below the linear transfer mechanism is provided with a material supporting frame 5 capable of storing a wafer tray. The linear transfer mechanism converts the wafer tray 4 between a clamping position and a transfer position of the wafer storage box 2; the transfer mechanism 6 is rotated to enable the wafer tray 4 to be switched between a transfer position and a processing transfer position on the cutting platform 7; the wafer vacuum chuck moving mechanism linearly moves the wafer tray 4 on the dicing table 7 in the X direction and the Y direction.
The linear transfer mechanism comprises a wafer clamping mechanism 3 and a clamping linear driving mechanism for driving the wafer clamping mechanism 3 to move linearly. A buffer anti-pinch device is arranged between the moving part of the clamping linear driving mechanism and the wafer clamping mechanism 3.
The moving member of the gripping linear drive mechanism includes a linear transfer slider 37; the linear transfer slider 37 is provided with a clamping slider 35, and the clamping slider 35 can move along the moving direction of the linear transfer slider 37. A clamping slide block return spring 38 is arranged between the clamping slide block 35 and the linear transfer slide block 37; the length of the clamping slider return spring 38 is along the direction of movement of the clamping slider 35. If the wafer clamping mechanism 3 clamps the wafer tray 4, in the process that the moving part continues to move forwards, the wafer tray 4 clamped by the wafer clamping mechanism 3 touches the inner wall of the wafer storage box 2 or a limiting strip in the wafer storage box, and the wafer clamping mechanism 3 can not move any more. At this time, the moving member continues to move, and relative movement is generated between the moving member and the wafer holding mechanism 3. With the structure, after the wafer holding mechanism 3 holds the wafer tray 4, the wafer tray 4 held by the wafer holding mechanism and the wafer storage box 2 cannot collide with each other. When the clamping linear driving mechanism moves to enable the wafer tray 4 clamped by the wafer clamping mechanism 3 to leave the wafer storage box 2, the clamping slide block return spring 38 ensures that the wafer clamping mechanism 3 moves backwards to enable the moving part and the wafer clamping mechanism 3 to reset. In the concrete structure, set up the spring mounting groove in the centre gripping slider 35, centre gripping slider reset spring 38 sets up in the spring mounting groove, one end is fixed with centre gripping slider 35, and the other end links to each other with the part that slider 37 stretched into in the spring mounting groove is transported to the straight line.
A clamping slide displacement detection mechanism is arranged between the clamping slide 35 and the linear transfer slide 37; namely, the linear transfer slider 37 is provided with the slider displacement sensor 370, and the corresponding position on the clamping slider 35 is provided with the slider displacement detection strip 350. Or a slide block displacement sensor 370 is arranged on the clamping slide block 35, and a slide block displacement detection strip 350 is arranged at a corresponding position on the linear rotating slide block 37. The clamping slide displacement detection mechanism is used for detecting whether the moving part and the wafer clamping mechanism 3 move relatively or not. Thereby judging whether the wafer tray 4 which can be clamped exists in the wafer storage box 2 at the height corresponding to the upper clamping plate 30 and the lower clamping plate 31 of the wafer clamping mechanism 3.
The wafer clamping mechanism 3 comprises a clamping connecting plate 34, the upper end of the clamping connecting plate 34 is fixedly connected with a clamping slide block 35, and the lower end is connected with an upper clamping plate 30 and a clamping cylinder 32; wherein the piston head of the clamping cylinder 32 is connected to the lower clamping plate 31. The front end part of the upper clamping plate 30 is provided with a downward clamping baffle 300, and a baffle avoiding groove 310 is arranged at the corresponding position of the lower clamping plate 31; the lower end of the holding flap 300 extends into the flap escape slot 310.
Or the wafer clamping mechanism 3 comprises a clamping connecting plate 34, the upper end of the clamping connecting plate 34 is fixedly connected with a clamping slide block 35, and the lower end is connected with an upper clamping plate 30 and a clamping cylinder 32; wherein the piston head of the clamping cylinder 32 is connected to the lower clamping plate 31. The front end part of the lower clamping plate 31 is upwards provided with a clamping baffle, and a baffle avoiding groove is arranged at the corresponding position of the upper clamping plate 30; the upper end of the clamping separation blade extends into the separation blade avoiding groove. The retaining tabs 300 may be used to position the wafer tray 4 in the wafer retaining mechanism 3. At this time, the upper clamping plate 30 and the lower clamping plate 31 may be closed to clamp the tray wafer 4 until the slider displacement sensor 370 detects the presence of the slider displacement detection bar 350. The structure of the clamping block piece 300 ensures that the slider displacement sensor 370 not only can detect whether the wafer clamping mechanism 3 is clamped empty, but also can ensure that the rear end of the wafer tray 4 is in contact with the clamping block piece 300 under the non-clamping state, thereby ensuring the accurate front and rear positions of clamping.
The clamping linear driving mechanism is a linear transfer screw rod mechanism 36, and a clamping linear transfer slide rail 39 is arranged on the outer side of the linear transfer clamping screw rod mechanism 36; the linear transfer slide 37 is slidably disposed on the clamping linear transfer slide 39. The linear transfer slider 37 may be directly connected to the nut of the linear rotation screw mechanism. The section of the clamping linear transfer sliding rail 39 is not circular, and the moving process is more stable.
A clamping plate spring 33 may be disposed between the upper clamping plate 30 and the lower clamping plate 31. The clamping plate spring 33 has one end fixed to the upper clamping plate 30 and the other end fixed to the lower clamping plate 31. The clamping force of the upper clamping plate 30 and the lower clamping plate 31 is adjusted by adjusting the elastic force of the clamping plate spring 33, and the buffering is provided in the clamping process, so that the wafer tray 4 is effectively protected.
Further, the rear end of the upper clamping plate 30 is also provided with a clamping cylinder avoiding groove 302, the clamping cylinder 32 is arranged in the clamping cylinder avoiding groove 302, and the piston head of the clamping cylinder 32 is connected with the clamping cylinder slider 320, the clamping cylinder slider 320 and a guide rail on the outer surface of the clamping cylinder 32 to form a guide rail slider connecting pair. The lower clamping plate 31 is fixed to a clamping cylinder slide 32. The clamp cylinder slider 320 may be L-shaped. The clamping plate spring 33 may be disposed between the upper surface of the clamping cylinder slider 320 and the lower surface of the cylinder body of the clamping cylinder 32. Or between the upper and lower clamping plates 30 and 31 on both sides of the clamping cylinder escape groove 302.
The clamping plate spring 33 is a tension spring, the clamping cylinder 32 is a double-acting cylinder, one end of the double-acting cylinder is selectively communicated with an air source or atmosphere, and the other end of the double-acting cylinder is directly communicated with the atmosphere. The clamp cylinder 32 is now able to extend for ventilation and requires external force to retract when ventilation is no longer required. During ventilation, the clamping cylinder 32 drives the lower clamping plate 31 to move downwards. When the ventilation is not performed, the tension spring pulls the lower clamping plate 31 back to reset. In a clamping state; the extension amount of the tension spring is larger than that of the lower clamping plate 31 corresponding to the gravity. At this time, the restoring force of the tension spring is greater than the gravity of the lower clamping plate 31, so that the lower clamping plate 31 and the upper clamping plate 30 press the wafer tray 4. A plurality of tension springs or a tension spring having a large elastic force may be provided to increase the elastic force thereof to clamp the wafer tray 4. The tension springs with different elastic forces can provide different clamping forces.
The clamp cylinder 32 may also be a single-acting cylinder. The single-acting cylinder is internally provided with a spring so that the single-acting cylinder can extend when in ventilation and automatically retract when not in ventilation. However, the cylinder is a standard component, the elasticity of the spring in the single-action cylinder is fixed, the restoring force is small and cannot be adjusted, and the clamping force capable of being applied is also fixed. After the standard cylinder with the required telescopic length is selected, the restoring elasticity of the built-in spring cannot accurately meet the requirement of the wafer clamping mechanism 3. And the clamping force required by the different gravity of the wafer trays 4 with different specifications is different, so that a mechanism for conveniently adjusting the elasticity is required. The clamp plate spring 33 needs to be provided even for the single-acting cylinder.
In order to detect whether the wafer tray is in place during clamping and prevent the phenomenon of empty clamping, the upper clamping plate 30 may also be provided with a clamping plate displacement sensor 301, and the lower clamping plate 31 is provided with a clamping plate displacement detection strip 311 matched with the upper clamping plate. Further, the method comprises the following steps: the clamping plate displacement sensor 301 is located at the side edge of the upper clamping plate 30, and one end of the clamping plate displacement detection strip 311 is fixed on the clamping cylinder slider 320.
When the upper clamping plate 30 and the lower clamping plate 31 are in a hollow state, the clamping plate spring 33 pulls the lower clamping plate 31 back, the elasticity of the clamping plate spring 33 ensures that the upper clamping plate 30 and the lower clamping plate 31 are contacted and have pressure, and at the moment, a clamping plate displacement detection strip 311 is inserted between the transmitting end and the receiving end of the clamping plate displacement sensor 301; when the clamping plate is not empty, the receiving end of the clamping plate displacement sensor 301 can receive the signal sent by the transmitting end. The clamping plate displacement sensor 301 may be a photo sensor.
The slider displacement sensor 370 can detect whether the wafer tray 4 is in place in the front-rear direction. After the wafer tray is detected to be in place, the clamping cylinder 32 starts to act to clamp, and the clamping plate displacement sensor 301 can detect whether the upper position and the lower position of the lower clamping plate are in place or not and whether the wafer tray 4 is clamped together with the upper clamping plate 30 or not.
The wafer storage box 2 capable of moving up and down is arranged on the rack 1, a horizontal material supporting groove corresponding to the wafer tray 4 is arranged on two side walls of the wafer storage box 2, which are located in the insertion direction of the wafer tray 4, and the wafer tray can be placed in the horizontal material supporting groove. And limiting rods which can slide along the front and back directions of the horizontal material supporting groove are further arranged on the two side walls of the wafer material storage box 2, and the length of each limiting rod is approximately equal to the height of the wafer material storage box 2. The wafer tray 4 stops moving when moving to contact with the limit rod. The wafer tray 4 stores individual silicon wafers, and the wafer tray 4 is brought into contact with a jig or a chuck during wafer carrying and laser dicing. The wafer tray 4 comprises a circular metal disc, four straight edges are arranged on the circular metal disc, and the four straight edges are respectively located at four end points of the cross. One of the straight edges is a clamping end for clamping the wafer tray, and the other straight edge is arranged on the opposite side of the clamping end. The other two straight edges are contacted with the horizontal material supporting groove. The wafer cassette is generally configured as a rectangular parallelepiped. The center of the metal disc is provided with a center hole, the center hole is covered with a bearing layer, and the wafer is arranged on the bearing layer. The shapes and structures of the wafer tray 4 and the wafer magazine 2 are prior art and will not be described in detail.
The rotary transfer mechanism 6 comprises a transfer connecting body 60 which is rotatably arranged on the frame 1, and the transfer connecting body 60 is downwards connected with a transfer sucker 64 which can be lifted. Transport connector 60 both ends and set up respectively and transport lift cylinder 61, transport lift cylinder 61's lateral surface setting and transport lift cylinder guide rail 66, transport lift cylinder 61's fixed cylinder connecting plate 62 of transporting of piston head. The transfer cylinder connecting plate 62 fixes the transfer lifting cylinder slide block 65; the transfer lifting cylinder slide block 65 and the transfer lifting cylinder guide rail 66 form a guide rail pair. A cantilever 63 extends out of the outer side of the transfer lifting cylinder slide block 65, and a transfer sucker 64 is fixed on the cantilever 63. The transfer lifting cylinder 61 drives the transfer sucker 64 to lift, and the position where the piston head moves has certain deviation, so that the position of the transfer sucker 64 has certain error, and subsequent processing procedures are influenced. A transfer lifting cylinder guide rail 66 is arranged on the outer side surface of the transfer lifting cylinder 61, and a transfer sucker 64 is fixed together with a transfer lifting cylinder slide block 65 through a cantilever 63; the position of the transfer sucker in the lifting process is accurate through the guide rail pair structure. And two transfer lifting cylinders can make wafer tray 4 transport the position and transport the position with processing and exchange between, and wafer tray 4 after the processing is accomplished need not to remove from other route, can return to wafer storage box 2 on the original way, compact structure.
The transfer connector 60 is provided with a transfer displacement detection strip 67; two transfer displacement sensors 68 are disposed on the frame 1 along the rotation locus of the transfer displacement detection bar 67. When the transfer displacement detection strip 67 is moved from one transfer displacement sensor 68 to the other transfer displacement sensor 68, one of the transfer suction cups 64 moves from the transfer position to the processing transfer position, and the other transfer suction cup moves from the processing transfer position to the transfer position. The transfer displacement sensor 68 ensures that the transfer chuck 64 is accurately stopped at the transfer position and the processing transfer position. As for the middle obstacle avoidance position, the precision is not required, the operation can be realized only by rotating a certain angle from the transfer position or the machining transfer position, and the operation can be realized through a servo motor.
The transfer connector 60 is connected to the output of a transfer motor provided on the frame 1. Set up annular transportation spacing groove around the axis of transporting the motor output shaft in frame 1, set up the lower extreme in the transportation spacing groove and fixed with the transportation connector 60, the upper end passes the transportation spacing post 69 of transporting the spacing groove, and the angle of transporting the spacing groove is guaranteed to transport spacing post 69 and is rotated 180 degrees. The transfer limiting groove can be slightly larger than 180 degrees. When the transfer limiting column 69 is positioned at two ends of the transfer limiting groove, one of the two transfer suckers is positioned at the transfer position.
The transfer sucker 64 comprises a sucker frame body, at least 3 downward sucker rods 642 are circumferentially arranged on the sucker frame body, and a negative pressure sucker 643 is arranged on each sucker rod 642; the suction head rod 642 is provided with a gas connector communicated with the negative pressure suction nozzle, and the gas connector is connected with a negative pressure source through a negative pressure pipe. How the negative pressure is achieved in the transfer cup 64 is known in the art and will not be described in detail.
The sucking disc frame body comprises a cross frame body 640, a frame body connecting plate 641 is arranged at the tail end of the cross frame body 640, and the upper end of the sucking head rod 642 is fixed on the frame body connecting plate 641; the frame connecting plate 641 is provided with an adjusting groove 645, the cross frame 640 is provided with a fixing hole, and the length of the frame connecting plate 641 extending out of the cross frame 640 is adjusted by adjusting the position of the fixing hole in the length direction of the adjusting groove 645. The fixing hole may be a screw hole, a bolt is disposed in the fixing hole, and the frame body connecting plate 641 and the cross frame body 640 are fixed by pressing the upper surface of the connecting plate with a nut of the bolt.
The material supporting frame 5 comprises a material supporting bottom plate 53, two parallel material supporting guide rails 51 are arranged on the material supporting bottom plate 53, the material supporting guide rails 51 are driven by a guide rail driving mechanism to be opposite along the material supporting bottom plate 53 or to be a synchronous belt conveying mechanism arranged on the material supporting bottom plate 53, a synchronous belt connecting plate 55 is fixed on each of two synchronous belts 54 on two sides of the synchronous belt conveying mechanism respectively, the two synchronous belt connecting plates 55 move oppositely or oppositely, and each synchronous belt connecting plate 55 is connected with one material supporting guide rail 51. The synchronous belt conveying mechanism comprises a synchronous belt motor arranged on the material supporting bottom plate 53, a chain wheel is arranged on an output shaft of the synchronous belt motor, a rotating chain wheel is also arranged on one side, far away from the synchronous belt motor, of the material supporting bottom plate 53, and a synchronous belt 54 is arranged on the chain wheel.
Two parallel material supporting bottom plate guide rails 59 are arranged on the material supporting bottom plate 53, and the length direction of the material supporting bottom plate guide rails 59 is vertical to the length direction of the material supporting guide rails 51; the bottom of the material supporting guide rail 51 is connected with a material supporting guide rail connecting plate 57, a connecting plate sliding block is arranged on the material supporting guide rail connecting plate 57, and the connecting plate sliding block and the material supporting bottom plate guide rail 59 form a guide rail pair; and the material supporting guide rail connecting plate 57 is fixed with the synchronous belt connecting plate 55.
Furthermore, at least one material supporting bottom plate displacement sensor 56 is arranged on the material supporting bottom plate 53, and a connecting plate displacement detection strip 58 corresponding to the material supporting bottom plate displacement sensor 56 is arranged on the synchronous belt connecting plate 55. When the connecting plate displacement detecting strip 58 moves to the position of each material supporting base plate displacement sensor 56, the distance between the two corresponding material supporting guide rails 51 corresponds to the size of one type of wafer tray 4. Web displacement sensing strips 58 may also be provided on the carrier rail web 57.
The material supporting guide rail 51 is provided with a proximity switch 52. A groove is arranged on the material supporting guide rail 51, the proximity switch 52 is arranged in the groove, and the upper surface of the proximity switch 52 is not higher than the upper surface of the material supporting guide rail 51. Thus, when the wafer tray 4 held by the wafer holding mechanism 3 reaches the position of the proximity switch 52, the proximity switch is turned on so that the wafer holding mechanism 3 does not move forward any more, and the wafer tray 4 is released to be placed on the two material holding rails 51. The wafer chuck 3 is then removed.
One end of the material supporting guide rail 51 can extend to a position close to the wafer storage box 2, and the length direction of the material supporting guide rail 51 is parallel to the linear moving direction of the wafer clamping mechanism 3 along the clamping linear transfer slide rail 39. Of course, the carrier rail 51 may be provided in another direction as long as it can support the wafer tray 4, but a mechanism capable of vertical adjustment is required in order to avoid interference with the wafer chucking mechanism 3.
The wafer vacuum chuck moving mechanism comprises a cutting platform 7, and an X sliding seat 70 which can move along the X direction on the cutting platform 7; an XY slide base 71 moving along the Y direction is arranged on the X slide base 70; a rotating seat 72 is arranged on the XY sliding seat 71; a wafer vacuum chuck 75 is disposed on the spin base 72. At least 3 piezoelectric ceramics 76 may be disposed between the spin base 72 and the wafer vacuum chuck 75. One end of the piezoelectric ceramic 76 is connected to the upper surface of the rotary base 72, and the other end is connected to the lower surface of the wafer vacuum chuck 75. The spin base 72 and the wafer vacuum chuck 75 are connected by a piezoelectric ceramic 76. A CCD detection mechanism for detecting the cutting condition is arranged above the machine frame 1 and can comprise a camera and a graphic processing system, and the CCD detection mechanism is electrically connected with the controller. The CCD detection mechanism photographs the upper surface of the wafer and processes and analyzes the wafer, and the result is sent to the controller. When the upper surface of the wafer is not a plane, the controller sends a signal to the piezoelectric ceramic 76, and adjusts the piezoelectric ceramic 76 to change its height so that the upper surface of the wafer does not tilt.
A fixed hemisphere 76 having a partial sphere outer surface may be fixedly disposed at a central position of an upper surface of the rotary base 72, and a fixed hemisphere hole corresponding to the fixed hemisphere 76 is disposed at a central position of a lower surface of the wafer vacuum chuck 75. The center of the fixed hemisphere 76 is on the axis of the turntable 72 and the wafer vacuum chuck. The fixed hemisphere 76 and the fixed hemisphere hole allow the wafer vacuum chuck 7 to rotate in multiple directions around the fixed hemisphere 76, thereby accommodating height adjustment of the piezoelectric ceramic 76.
A zero position positioning mechanism of the rotary seat 72 is arranged between the rotary seat 72 and the XY sliding seat 71. Specifically, a rotating seat displacement sensor is arranged on the side edge of the XY sliding seat 71, and a rotating seat displacement sensor detection strip is arranged at the position corresponding to the rotating seat 72. After the wafer tray that is processed each time is taken away, the rotary base 72 rotates to the zero position, that is, the rotary base displacement sensor senses the rotary base displacement sensor detection strip. After the unprocessed wafer tray moves on the wafer vacuum chuck 75 on the rotary base 72, the optical equipment can send a signal to enable the rotary base 72 to rotate to a proper position relative to the zero position after photographing and analyzing the unprocessed wafer tray. The upper surface of the wafer vacuum chuck 75 is provided with an adsorption groove, the adsorption groove is provided with a downward adsorption hole, and the adsorption hole is connected with the space where the vacuum generator is located. The structure of the wafer vacuum chuck 75 belongs to the prior art, and can be as in patent CN105321863A and other disclosed structures, which are not described in detail.
The X-direction and the Y-direction are perpendicular. The wafer tray is disposed above the rotary base 72 and moves with the rotary base 72. Generally, the position of the wafer tray on the rotary base 72 is determined by an optical device and a signal is sent to rotate the rotary base 72 by a proper angle, thereby positioning. The rotary table 72 can be rotated to ensure that the scribing direction on the wafer is parallel to the moving direction of the X slide table 70 and the moving direction of the XY slide table 71, respectively. Thus, the X slide holder 70 and the XY slide holder 71 can be moved at different times, and the saw teeth are not generated in the scribing direction during laser dicing, thereby improving the precision of laser dicing of silicon wafers. An X linear motor is arranged on the rack along the X direction; the X sliding seat 70 is fixed with a rotor of the X linear motor; an XY linear motor is arranged on the X sliding seat 70 along the Y direction, and the XY sliding seat 71 is fixed with the power of the XY linear motor. Two parallel X linear motors are arranged on the rack 1 in parallel, and two ends of an X sliding seat 70 are respectively arranged on the rotors of the X linear motors; two parallel XY linear motors are arranged on the X sliding seat 70 in parallel, and two ends of the XY sliding seat 71 are respectively arranged on the rotors of the two XY linear motors. The X-linear motor and XY-linear motor step distance may be 0.5 to 1 micron. The structure is actually one of high-precision two-dimensional linear motor platforms, and the rotary seat 72 is arranged on the high-precision two-dimensional linear motor platform. The method can particularly refer to the existing high-precision two-position linear motor platform product. The rotary base 72 is a high precision rotary platform. The specific results of the high-precision rotary platform which is the existing product on the market are not described in detail.