Polishing and leveling device and method for thinning large-area infrared detector chips

Abstract

This invention discloses a polishing and leveling device and method for thinning large-area infrared detector chips, ensuring consistent processing across chip areas and forming a good surface profile to improve the quality of large-area infrared detector chips. The polishing and leveling device includes: a polishing disc; a polishing pad laid on the polishing disc; a fixture body including a pressure control rod and a fixture disc, the bottom end of the pressure control rod being connected to the upper surface of the fixture disc, and the lower surface of the fixture disc being adapted to polish the chip in conjunction with the polishing pad; the fixture disc having multiple axially spaced through holes, each through hole housing a pressure block, the pressure block being axially movable relative to the through hole; the pressure block having an axially through suction hole; a drive system for driving the pressure control rod to move axially and rotate around an axis, and also for driving the pressure block to move axially; a vacuum pump having multiple suction pipes, each suction pipe corresponding to a suction hole; and a control system for controlling the drive system and the vacuum pump.

Description

Technical Field

[0001] This invention relates to the field of detector fabrication technology, and in particular to a polishing and leveling device and method for thinning large-area infrared detector chips. Background Technology

[0002] In recent years, focal plane array infrared detectors have entered a third-generation technology characterized by ultra-large scale, multispectral density, integration, and low cost. Ultra-large scale detectors place large demands on the size of traditional zinc-cadmium telluride substrates, and the thermal mismatch between the detector chip and the substrate material becomes increasingly prominent with increasing size. Molecular beam epitaxy of HgCdTe thin films on silicon can effectively solve these problems, making it a hot research topic for large-area infrared detectors.

[0003] To increase the photoelectric conversion efficiency of infrared detectors, a thinning process of the silicon substrate needs to be introduced before passivation to increase the flatness and cleanliness of the chip surface. However, due to the special physicochemical properties of silicon substrates, the silicon wafer will be twisted and warped after mechanical polishing, and the degree of warping is positively correlated with the mechanical action. This leads to inconsistent removal rates between the edges and the center of the silicon wafer during polishing, resulting in poor surface profile and affecting the performance of the infrared detector. Summary of the Invention

[0004] This invention provides a polishing and leveling device and method for thinning large-area infrared detector chips, which improves the surface shape effect of large-area infrared detector chips after thinning.

[0005] A polishing and leveling apparatus for thinning a large-area infrared detector chip according to an embodiment of the present invention includes:

[0006] Polishing disc;

[0007] A polishing pad is laid on the polishing disc;

[0008] The fixture body includes a pressure control rod and a fixture disk. The bottom end of the pressure control rod is connected to the upper surface of the fixture disk, and the lower surface of the fixture disk is adapted to cooperate with the polishing pad to polish the chip.

[0009] The clamping disc has a plurality of axially through holes arranged at intervals, and each axially through hole has a pressure block built in it. The pressure block is axially movable relative to the axially through hole. The pressure block has an axially through suction hole.

[0010] The drive system is used to drive the pressure control rod to move axially and rotate about an axis, and also to drive the pressure block to move axially;

[0011] A vacuum pump has multiple suction pipes, each suction pipe being connected to a corresponding suction port;

[0012] A control system for controlling the drive system and the vacuum pump.

[0013] According to some embodiments of the present invention, the lower surface of the clamping disk has multiple guide grooves.

[0014] According to some embodiments of the present invention, the plurality of guide channels include intersecting transverse channels and longitudinal channels.

[0015] According to some embodiments of the present invention, the plurality of axial through holes are arranged in an array.

[0016] According to some embodiments of the present invention, the pressure block has a plurality of air intake holes, which are arranged at intervals.

[0017] According to some embodiments of the present invention, the plurality of air intake holes are arranged in an array.

[0018] According to some embodiments of the present invention, the clamp body further includes a clamp ring, which is sleeved on the clamp disk and is axially movable relative to the clamp disk.

[0019] According to some embodiments of the present invention, the clamp ring is connected to the clamp disc by a spring.

[0020] According to some embodiments of the present invention, the drive system is also used to drive the polishing disc to rotate about an axis.

[0021] According to an embodiment of the present invention, a polishing and leveling method is implemented based on a polishing and leveling device for thinning large-area infrared detector chips as described above; the method includes:

[0022] The control system controls the vacuum pump according to the initial suction parameters so that the large-area infrared detector chip is attached to the lower surface of the fixture disk under the suction of the vacuum pump.

[0023] Adjust the initial suction parameters and set the first pressure parameter so that the large-area infrared detector chip remains flat on the lower surface of the fixture disk under the reasonable action of the suction force of each suction hole and the pressure of each pressure block.

[0024] The control system controls the drive system according to the rotation parameters and the second pressure parameters, so that the pressure control rod rotates around the axis and moves along the axis under the driving action of the drive system.

[0025] The present invention provides a polishing and leveling technology for large-area chips, which can significantly improve work efficiency, effectively reduce chip warpage, maintain a good surface shape, reduce the probability of damage, and increase the yield. The device and technology used are inexpensive and easy to operate.

[0026] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0027] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of the embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. In the drawings:

[0028] Figure 1 This is a partial structural diagram of the polishing and leveling device in an embodiment of the present invention;

[0029] Figure 2 This is a partial structural diagram of the polishing and leveling device in an embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the fixture body in an embodiment of the present invention;

[0031] Figure 4 This is a bottom view of the fixture body in an embodiment of the present invention;

[0032] Figure 5 This is a top view of the fixture body in an embodiment of the present invention;

[0033] Figure 6 This is a schematic diagram illustrating the interaction between the pressure block and the suction port in an embodiment of the present invention.

[0034] Figure label:

[0035] Polishing table 1, polishing disc 2,

[0036] Polishing pad 3,

[0037] Pressure control rod 4, clamping plate 5, pressure block 51, suction port 510, guide groove 52, vacuum pump 6, control system 7, clamping ring 8, suction / pressure control area a. Detailed Implementation

[0038] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art. Furthermore, in some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0039] Combination Figure 1 and Figure 2 As shown, the polishing and leveling device for thinning large-area infrared detector chips according to an embodiment of the present invention includes:

[0040] Polishing disc 2;

[0041] Polishing pad 3 is laid on polishing disc 2;

[0042] The fixture body includes a pressure control rod 4 and a fixture disk 5. The bottom end of the pressure control rod 4 is connected to the upper surface of the fixture disk 5. The lower surface of the fixture disk 5 is suitable for polishing the chip with the polishing pad 3. The lower surface of the fixture disk 5 and the upper surface of the polishing disk 2 ensure the required flatness.

[0043] The fixture disk 5 has multiple axially through holes arranged at intervals, each with a pressure block 51 embedded within it. The pressure block 51 is axially movable relative to the through hole. When the chip is located on the lower surface of the fixture disk 5, the pressure block 51 protrudes from the lower surface of the fixture disk 5 by moving downwards, applying pressure to the chip area at its relative position. The pressure block 51 has an axially through suction hole 510. The suction hole 510 creates a suction force on the chip area. Multiple pressure blocks 51, in conjunction with the suction hole 510, form a suction / pressure control zone a, as shown in the figure. Figure 3 and Figure 4 .

[0044] The drive system is used to drive the pressure control lever 4 to move axially (i.e., move closer to or away from the polishing disc 2) and rotate about the axis (rotate about the pressure control lever 4), and also to drive the pressure block 51 to move axially (rotate about the central axis of the pressure block 51).

[0045] Vacuum pump 6 has multiple suction pipes, each suction pipe being connected to a corresponding suction port 510, as shown in the reference. Figure 4 As shown;

[0046] Control system 7 is used to control the drive system and vacuum pump 6.

[0047] The present invention provides a polishing and leveling technology for large-area chips, which can significantly improve work efficiency, effectively reduce chip warpage, maintain a good surface shape, reduce the probability of damage, and increase the yield. The device and technology used are inexpensive and easy to operate.

[0048] Based on the above embodiments, further variant embodiments are proposed. It should be noted that, in order to keep the description brief, only the differences from the above embodiments are described in each variant embodiment.

[0049] like Figure 4As shown, according to some embodiments of the present invention, the lower surface of the jig disk 5 has multiple guide grooves 52. The guide grooves 52 are used to circulate the polishing slurry, improving the fluidity of the polishing slurry, thereby improving the thinning and polishing effects.

[0050] like Figure 4 As shown, according to some embodiments of the present invention, the multiple guide grooves 52 include intersecting transverse and longitudinal grooves. This ensures the uniform arrangement of the guide grooves 52, further improving the thinning and polishing effects.

[0051] Furthermore, multiple guide channels 52 can be distributed around the suction / pressure control zone a.

[0052] According to some embodiments of the present invention, a plurality of axially through holes are arranged in an array. This improves the uniformity of the pressure block 51's effective range. For example, in Figure 4 In the middle, nine axial through holes are distributed in an array.

[0053] According to some embodiments of the present invention, the pressure block 51 has a plurality of suction holes 510, which are arranged at intervals. This improves the uniformity of the effect of the suction holes 510.

[0054] In some embodiments of the present invention, multiple air intake holes 510 on a pressure block 51 are controlled by a single air intake pipe.

[0055] In other embodiments of the invention, each air intake 510 is independently controlled by an air intake tube.

[0056] According to some embodiments of the present invention, a plurality of air intake holes 510 are arrayed.

[0057] like Figures 1-2 , Figures 4-5 As shown, according to some embodiments of the present invention, the fixture body further includes a fixture ring 8, which is fitted over the fixture disk 5 and is axially movable relative to the fixture disk 5. The fixture ring 8 can act as a barrier between the polishing slurry and the chip, confining the polishing slurry within the fixture ring 8, and ensuring that the chip remains within the fixture ring 8.

[0058] According to some embodiments of the present invention, the clamp ring 8 is connected to the clamp disk 5 by a spring.

[0059] According to some embodiments of the present invention, the drive system is also used to drive the polishing disc 2 to rotate about an axis. The polishing disc 2 can be disposed on the polishing table 1, and the polishing disc 2 can rotate in the opposite direction to the fixture disc 5 under the action of the drive system, so as to improve the thinning and polishing efficiency.

[0060] According to some embodiments of the present invention, the polishing and leveling device of the present invention can be applied to the thinning and polishing of large-area silicon-based infrared detector chips.

[0061] According to an embodiment of the present invention, a polishing and leveling method is implemented based on a polishing and leveling device for thinning large-area infrared detector chips as described above; the method includes:

[0062] The control system controls the vacuum pump according to the initial suction parameters so that the large-area infrared detector chip is attached to the lower surface of the fixture disk under the suction of the vacuum pump.

[0063] Adjust the initial suction parameters and set the first pressure parameter to ensure that the large-area infrared detector chip remains flat on the lower surface of the fixture disk under the combined suction force of each suction port and the pressure of each pressure block; refer to Figure 6 As shown, when one area of ​​the chip protrudes, a downward pressure is applied to that area through the pressure block corresponding to that area; when another area of ​​the chip is recessed, an upward suction force is applied to that area through the air intake hole corresponding to that area.

[0064] The control system controls the drive system according to the rotation parameters and the second pressure parameters, so that the pressure control rod rotates around the axis and moves along the axis under the driving action of the drive system.

[0065] The text-to-speech processing apparatus and text-to-speech processing method according to the present invention will now be described in detail with reference to the accompanying drawings and a specific embodiment. It is to be understood that the following description is merely exemplary and should not be construed as a specific limitation of the present invention.

[0066] Combination Figure 1 and Figure 2 As shown, the polishing and leveling device for thinning large-area infrared detector chips according to an embodiment of the present invention includes:

[0067] Polishing table 1;

[0068] Polishing disc 2 is placed on polishing table 1;

[0069] Polishing pad 3 is laid on polishing disc 2;

[0070] The fixture body includes a pressure control rod 4 and a fixture disk 5. The bottom end of the pressure control rod 4 is connected to the upper surface of the fixture disk 5. The lower surface of the fixture disk 5 is suitable for polishing the chip with the polishing pad 3. The lower surface of the fixture disk 5 and the upper surface of the polishing disk 2 ensure the required flatness.

[0071] The fixture disk 5 has multiple axially through holes arranged at intervals, each with a pressure block 51 embedded within it. The pressure block 51 is axially movable relative to the through hole. When the chip is located on the lower surface of the fixture disk 5, the pressure block 51 protrudes from the lower surface of the fixture disk 5 by moving downwards, applying pressure to the chip area at its relative position. The pressure block 51 has an axially through suction hole 510. The suction hole 510 creates a suction force on the chip area. Multiple pressure blocks 51, in conjunction with the suction hole 510, form a suction / pressure control zone a, as shown in the figure. Figure 3 and Figure 4 .

[0072] like Figure 4 As shown, the lower surface of the fixture disk 5 has multiple guide grooves 52. The guide grooves 52 are used to flow the polishing slurry, improving its fluidity and thus enhancing the thinning and polishing effects. The multiple guide grooves 52 include intersecting transverse and longitudinal grooves. This ensures the uniform arrangement of the guide grooves 52, further improving the thinning and polishing effects. The multiple guide grooves 52 can be distributed around the suction / pressure control zone a.

[0073] Multiple axial through holes are arrayed. This improves the uniformity of the pressure block 51's effective range. The pressure block 51 has multiple suction holes 510, which are arranged at intervals. The multiple suction holes 510 on a single pressure block 51 are uniformly controlled by a single suction pipe. The multiple suction holes 510 are arrayed.

[0074] A clamping ring 8 is fitted over the clamping disk 5 and is axially movable relative to the clamping disk 5. The clamping ring 8 acts as a barrier between the polishing slurry and the chip, confining the polishing slurry within the clamping ring 8 and ensuring the chip remains within the clamping ring 8. The clamping ring 8 is connected to the clamping disk 5 by a spring.

[0075] The drive system is used to drive the pressure control lever 4 to move axially (i.e., move closer to or away from the polishing disc 2) and rotate around its axis (rotate around the pressure control lever 4), and also to drive the pressure block 51 to move axially (rotate around the central axis of the pressure block 51); the drive system is also used to drive the polishing disc 2 to rotate around its axis. The polishing disc 2 can be set on the polishing table 1, and the polishing disc 2 can rotate in the opposite direction to the clamping disc 5 under the action of the drive system to improve the thinning and polishing efficiency.

[0076] Vacuum pump 6 has multiple suction pipes, each suction pipe being connected to a corresponding suction port 510, as shown in the reference. Figure 4 As shown;

[0077] Control system 7 is used to control the drive system and vacuum pump 6.

[0078] The width and shape of the guide groove 52 can be adjusted according to the actual use, the size of the suction / pressure control area a can be adjusted according to the chip size, and the number and size of the pressure block 51 and the vacuum suction hole 510 can be adjusted according to the actual use. To prevent the chemical components in the polishing fluid from affecting the suction / pressure control area a, the pressure block 51 is surrounded by a foot sleeve made of corrosion-resistant material.

[0079] The method of using the polishing and leveling device for thinning large-area infrared detector chips according to an embodiment of the present invention is as follows: During the chip polishing process: 1) Place the cleaned chip in the suction / pressure control area; 2) Run the vacuum pump to firmly attach the chip to the suction / pressure control area; 3) Level the chip according to its warpage, appropriately increasing the suction force of the vacuum suction hole for the protruding part of the chip and appropriately increasing the pressure of the pressure block for the concave part of the chip; 4) Run the polishing machine to rotate the fixture on the polishing pad and press down on the main body of the guide groove area; 5) After polishing, remove the chip and move it into other fixtures according to the process requirements, repeating steps 1)-5) until the polishing process standard is met.

[0080] Compared with existing technologies, the present invention has the following technical advantages: 1) It realizes polishing and leveling technology for large-area chips, greatly improving work efficiency; 2) It effectively reduces chip warpage, maintains a better surface shape, reduces the probability of damage, and improves the yield; 3) The equipment and technology used are inexpensive and easy to operate.

[0081] It should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0082] It should be noted that any content not described in detail in this specification is common knowledge to those skilled in the art.

Claims

1. A polishing leveling device for thinning a large array infrared detector chip, characterized in that, The polishing device comprises: a polishing disc; a polishing pad laid on the polishing disc; a clamp body comprising a pressure control rod and a clamp disc, a bottom end of the pressure control rod being connected to an upper surface of the clamp disc, a lower surface of the clamp disc being adapted to cooperate with the polishing pad to polish a chip; the clamp body further comprises a clamp ring, the clamp ring being sleeved on the clamp disc and being axially movable relative to the clamp disc; the clamp ring is connected to the clamp disc through a spring; the clamp disc has a plurality of axially-through holes arranged at intervals, each of the axially-through holes being provided with a pressure block, the pressure block being axially movable relative to the axially-through hole; the pressure block has an axially-through air suction hole; the lower surface of the clamp disc has a plurality of flow guide grooves; the flow guide grooves comprise transverse grooves and longitudinal grooves which cross each other; a driving system for driving the pressure control rod to move axially and rotate about an axis, and for driving the pressure block to move axially; a vacuum pump having a plurality of air suction pipes, each of the air suction pipes being connected to one of the air suction holes; a control system for controlling the driving system and the vacuum pump.

2. The polishing leveling device for thinning large area array infrared detector chip of claim 1, wherein, The plurality of axially-through holes are arranged in an array.

3. The polishing leveling device for thinning large area array infrared detector chip of claim 1, wherein, The pressure block has a plurality of the air suction holes, the air suction holes being arranged at intervals.

4. The polishing leveling device for thinning large area array infrared detector chip of claim 3, wherein, The plurality of air suction holes are arranged in an array.

5. The polishing leveling device for thinning large area array infrared detector chips of claim 1, wherein, The driving system is further used to drive the polishing disc to rotate about an axis.

6. A method of polishing leveling, characterized by, The polishing leveling method is implemented based on the polishing leveling device for thinning a large-array infrared detector chip according to any one of claims 1-5; the method comprises: a control system controls a vacuum pump according to initial air suction parameters, so that the large-array infrared detector chip is attached to a lower surface of a clamp disc under the suction force of the vacuum pump; the initial air suction parameters are adjusted, and a first pressure parameter is set, so that the large-array infrared detector chip is kept flat on the lower surface of the clamp disc under the reasonable combined action of the suction force of each air suction hole and the pressure of each pressure block; a control system controls the driving system according to rotation parameters and a second pressure parameter, so that the pressure control rod rotates about an axis and moves along the axis under the driving action of the driving system.

Images