CN102751228A

CN102751228A - Wafer clamping device by utilizing spring pinch cock

Info

Publication number: CN102751228A
Application number: CN2012102188529A
Authority: CN
Inventors: 杨开明; 朱煜; 李鑫; 汪劲松; 尹文生; 胡金春; 张鸣; 徐登峰; 穆海华; 崔乐卿; 余东东
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2011-06-28
Filing date: 2012-06-27
Publication date: 2012-10-24
Anticipated expiration: 2032-06-27
Also published as: WO2013000420A1; CN102751228B; CN202678300U

Abstract

The invention discloses a wafer clamping device by utilizing a spring pinch cock, which comprises a V-shaped tray of a slice, wafer clips and bulge supports, wherein each wafer clip comprises a bracket, a connecting rod, a spring and a sliding block; when a wafer is grabbed, the edge of the wafer contacts with the slope parts of the sliding blocks; the sliding blocks move along the connecting rods towards the bracket direction by the gravity component of the wafer; the springs are compressed; the wafer is clamped between the wafer clips; the bottom surface of the wafer contacts with the upper surfaces of four extruded pieces and is supported by the extruded pieces; the edge of the wafer contacts with the side surfaces of the sliding blocks; the deformation of the springs generates certain pressure on the edge of the wafer; and the wafer is clamped to fix. The transmission of wafers of different diameter sizes can be realized by changing the position of the wafer clips on the tail end of the tray. The system flexibility is increased by the springs, and wafer damage caused by the rigid contact of the tray and the edge of the wafer in the transmission process can be avoided. When the wafer is grabbed, the wafer falls in the inclined part range of the sliding blocks to satisfy the requirement, and therefore, an end effector is permitted to have a certain positioning error.

Description

A kind of wafer clamping device that utilizes spring clip

Technical field

The present invention relates to the wafer clamping device, be mainly used in the semiconductor crystal wafer process equipment, belong to the ultraprecise manufacture field.

Background technology

In semiconductor fabrication, like the cleaning of wafer, polishing etc., between film magazine-film magazine, film magazine-chamber, there are a large amount of transmission that wafer is carried out, therefore designing a kind of clamping device of wafer safely and effectively is one of focus of semicon industry research.

The wafer transfer device of patent US2006/0182561A1 is shown in Figure 10 (a), Figure 10 (b).Wafer pallet 20 has

circular groove

24, and 21a, 22a, 24a, 24b are step cutting pattern.When pallet grasped and transmits wafer, the wafer bottom surface contacted with the surface of

step

24a, 24b, and 24a, 24b play the effect of support to wafer.The contacts side surfaces of the edge of wafer and step 21a, step 22a has limited moving of wafer level direction.This device can be used for the transmission of semicon industry wafer; But there is certain deficiency in this structure: the size of circular groove 24,

step

21a, 22a, 24a, 24b that 1. is used for fixing wafer is fixing; Therefore this device receives the restriction of diameter wafer size, can only transmit the wafer of fixed size.2. in the high-speed transfer process, the side of

step

21a, 22a contacts with the crystal round fringes rigidity and bumps, and makes wafer breakage easily.3. when grasping silicon wafer, if there is position error in arm end effector, wafer can not drop on

step

24a, 24b is last, in transmission course, will wafer come off.

Patent US6276731B1 wafer transfer device is shown in figure 11.The wafer carrying district is 2, and 2 places process the circular groove with step at supporting region, is respectively step 3, step 4.The internal diameter of step 3 is bigger slightly than wafer, and height equates that with wafer thickness step 4 internal diameters are bigger than diameter wafer, and height equates with wafer thickness.Utilize the side of step to contact and limit its horizontal movement, reach fixing purpose with the outward flange of wafer.Different with patent US2006/0182561A1 is; In this structure; The wafer outward flange is and the contacts side surfaces of the step 3 of circular groove below, and the benefit of design is like this, even aligning (like Figure 11 b) not during grasping silicon wafer; Also can utilize the side of step 4 to limit its motion, guarantee that wafer can landing when transmission.But this structure comes with some shortcomings: 1. be in the high-speed transfer process, the wafer side contacts with the step side rigidity and bumps, and makes wafer breakage easily; 2. the size of step 3, step 4 is fixing, so this device receives the restriction of diameter wafer size, can only transmit the wafer of fixed size.

Summary of the invention

The present invention has designed a kind of wafer clamping device that utilizes spring clip; Purpose is to allow end effector when grasping silicon wafer, to have certain position error; And in transmission course, reduce collision degree to crystal round fringes; Avoided because the wafer breakage that pallet causes the collision of crystal round fringes, this device does not receive the restriction of diameter wafer size simultaneously.

Technical scheme of the present invention is following:

A kind of wafer clamping device that utilizes spring clip is characterized in that: said device contains a thin slice V-type pallet, and pallet left end and right-hand member respectively are equipped with two wafer clips and two protruding back-up blocks; Four wafer clips on average be arranged in one with the concentric circumference of wafer on; Four protruding support on average be arranged in soon one with the concentric circumference of wafer on; Respectively there are two screwed holes pallet right-hand member both sides, and two wafer clip positions of pallet right-hand member are installed in the different screwed holes according to the difference of diameter wafer size and adjust; Protruding back-up block upper surface is the plane, in order to supporting wafer; Each wafer clip comprises support, connecting rod, spring and slide block; Support is cylindrical, with thin slice V-type pallet for being threaded; Slide block has through hole, moves as straight line along connecting rod, and the slide block side is made up of sloping portion and vertical component; Connecting rod one end is fixedly connected with support, other end support slipper; Spring housing is on connecting rod, and an end is fixedly connected with support, and the other end is fixedly connected with slide block.

The present invention has the following advantages and the high-lighting effect: when wafer hold up by the time, as long as wafer is dropped in the sloping portion scope of slide block, therefore when grasping silicon wafer, there is certain position error in the permission end effector.Adopt the flexible member to have increased the flexibility of device, the breakage of having avoided in the transmission course collision to crystal round fringes to cause.The position of the wafer clip that pallet is terminal can be adjusted, so this device is not transmitted the restriction of diameter wafer size.

Description of drawings

Fig. 1 is the vertical view of wafer clamping device of the present invention.

Fig. 2 is the end view of wafer clamping device shown in Figure 1.

Fig. 3 (a) is the local amplification plan view of wafer clip.

Fig. 3 (b) is the local enlarged front view of wafer clip.

When Fig. 4 is grasping silicon wafer and the instantaneous contact condition figure of crystal round fringes.

Fig. 5 is wafer stationary state figure in the transmission course.

Fig. 6 (a) is wafer clip size and diameter wafer size relationship figure.

Fig. 6 (b) is wafer clip size and diameter wafer size relationship figure.

Fig. 7 is the wafer clip figure that can rotate to an angle.

Fig. 8 is that wafer clip axis is through the figure of crystal circle center.

Fig. 9 is slide block height dimension requirement figure.

Figure 10 a, 10b are the wafer transfer structure drawing of device of patent US2006/0182561A1.

Figure 11 a, 11b, 11c are the wafer transfer structure drawing of device of patent US6276731B1.Among the figure:

101-thin slice V-type pallet; The 102-support; The 103-slide block; The 103a-sloping portion; The 103b-vertical component; The 104-connecting rod; The 105-spring; The protruding back-up block of 106-; The 107-screwed hole; 108-wafer clip; The 109-wafer;

Embodiment

Below in conjunction with accompanying drawing embodiment of the present invention is described in further detail.

Fig. 1, Fig. 2 are the principle schematic as a result (vertical view and end view) of wafer clamping device provided by the invention; This clamping device contains a thin slice V-type pallet 101; Pallet top and end respectively are equipped with two wafer clips 108 and two protruding back-up blocks 106; Thin slice V-type pallet 101 terminal both sides have 2-3 screwed hole 107 respectively; According to the difference of wafer 109 sizes, thin slice V-type pallet 101 two terminal wafer clip 108 positions can be installed in according to the difference of diameter wafer size in the different screwed holes to be adjusted.Protruding back-up block 106 upper surfaces are the plane, in order to supporting wafer.Wafer clip 108 is made up of support 102, connecting rod 104, spring 105 and slide block 103, and support 102 is cylindrical, with thin slice V-type pallet 101 for being threaded, and can rotate a certain angle.Slide block 103 has through hole 103c; Make the slide block 103 can be along connecting rod 104 moving linearlies, there be sloping portion 103a and vertical component 103b in the side, and wafer falls along sloping portion; Final its edge contacts with vertical component, makes 109 of wafers fixing between four slide blocks.Connecting rod 104 1 ends are fixedly connected with support, other end support slipper.Spring 105 is enclosed within on the connecting rod 104, and an end and support 102 are fixing, and the other end and slide block 103 are fixing, and when slide block 103 moved, spring 105 produced distortion, produced certain pressure through 103 pairs of wafer 109 edges of slide block, makes wafer 109 fixing.

Respectively there is a protruding strutting piece 106 both sides, pallet top, and its position is near the wafer clip, and relative wafer clip is near the inboard of pallet; In the terminal both sides of pallet a convexity 106 is arranged respectively, for cylindric, end face 106a is that plane and circumference carry out chamfering, with pallet also can be for being threaded for bonding.When supporting wafer 109, end face 106a contacts with supporting wafer with wafer 109 bottom surfaces.

At first when wafer 109 is held up by pallet, as shown in Figure 4, wafer 109 at first with four wafer clips in the sloping portion of slide block contact.Wafer 109 will move downward under action of gravity, because the 103a place is skewed, so the component of wafer 109 gravity makes slide block 103 move to the holder orientation straight line along connecting rod 104, compresses spring 105 simultaneously.

As shown in Figure 5; When wafer 109 continued to move downward, slide block 103 had moved certain distance along connecting rod 104, and wafer 109 drops between four slide blocks; This moment slider surface 103b and wafer 109 EDGE CONTACT; Limited the horizontal movement of wafer 109, the wafer bottom surface contacts with the end face 106a of four protruding supports 106, is supported by four projection pieces 106.In such structure, wafer 109 is sandwiched in the middle of four wafer clips, because the distortion of spring 105 produces certain chucking power to wafer 109, can make wafer 109 fixing.

Before transmission wafer 109; Should adjust the position of connecting rod 104 length, spring 105 length and terminal wafer clip according to the diameter dimension of wafer 109; Make that when grasping silicon wafer 109 wafer 109 can drop in the sloping portion 103a scope of slide block 103.Shown in Fig. 6 (a), Fig. 6 (b), suppose that wafer 109 diameters are D, should make D1 < D < D2.If D D1, the then crystal round fringes effect that can not be under pressure, and then can not limit the horizontal movement of wafer 109.If D>D2, then wafer 109 can not drop between four clips, and wafer 109 will be come off.

As shown in Figure 7, adjustment support 102 can make the wafer clip β that rotates to an angle.For making wafer 109 stressed even, the deflection of each clip medi-spring 105 should equate that promptly the amount of movement of slide block 103 should equate, so should adjust the angle of support 102, makes the center of the axis of each clip through wafer 109.As shown in Figure 8.

When wafer 109 dropped to protruding strutting piece 106 surfaces, its bottom surface contacted with 106a, is supported by four projection pieces 106.If limit the motion in its horizontal plane, should make 103a and its EDGE CONTACT.As shown in Figure 9, the distance of establishing sloping portion 103a bottom and tray upper surface is L1, and the bottom of vertical component 103b and tray upper surface distance are L2; When wafer 109 is supported by protruding 106; The upper surface of wafer 109 and the distance of tray upper surface are H1, and the lower surface of wafer 109 and the distance of tray upper surface are H2, should satisfy following relation between each size; Be L1>H1, L2 < H2.

Therefore slide block 103 and spring 105 can change the fixedly thrust of wafer 109 of wafer clip through the stiffness coefficient that changes spring 105 length or spring 105 for being fixedly connected, and avoids pressure to cross ambassador's wafer breakage.

The present invention when holding up wafer 109, as long as wafer 109 is dropped in the sloping portion 103a scope of slide block 103, therefore when grasping silicon wafer 109, allows end effector to have certain position error owing to adopted above technical scheme.Adopt the flexible member to have increased the flexibility of device, avoided the breakage of the wafer that pallet in the transmission course causes the collision at wafer 109 edges.Two terminal wafer clip positions can be adjusted, so this device is not transmitted the restriction of diameter wafer size.

Claims

1. wafer clamping device that utilizes spring clip, it is characterized in that: said device contains a thin slice V-type pallet (101), and pallet left end and right-hand member respectively are equipped with two wafer clips (108) and two protruding back-up blocks (106); Four wafer clips (108) on average be arranged in one with the concentric circumference of wafer on; Four protruding support fast (106) on average be arranged in one with the concentric circumference of wafer on; Respectively there are two screwed holes pallet right-hand member both sides, and two wafer clips (108) position of pallet right-hand member is installed in the different screwed holes according to the difference of diameter wafer size and adjusts; Protruding back-up block (106) upper surface is the plane, in order to supporting wafer; Each wafer clip (108) comprises support (102), connecting rod (104), spring (105) and slide block (103); Support (102) is cylindrical, with thin slice V-type pallet (101) for being threaded; Slide block (103) has through hole, moves as straight line along connecting rod (104), and slide block (103) side is made up of sloping portion and vertical component; Connecting rod (104) one ends are fixedly connected other end support slipper with support; Spring (105) is enclosed within on the connecting rod (104), and an end is fixedly connected with support (102), and the other end is fixedly connected with slide block (103).