CN104201135B - A kind of wet etch processor and its application method - Google Patents

Abstract

The present invention provides a wet etching device, the wet etching device includes a base, a liner and a vacuum generating device, the base is provided with an air flow channel communicating with the vacuum generating device, the substrate There is a groove inside, and the bottom of the groove is provided with through holes communicating with the air flow channel and corresponding to each other, and the edge of the bottom of the groove is provided with an arc-shaped slope matching the arc-shaped area of the edge of the wafer. The wet etching device can realize the corrosion of the entire back of the wafer; it can make the front of the entire wafer closely adhere to the liner, preventing the corrosion liquid from penetrating into the front of the wafer, effectively The front side of the wafer is protected from being in contact with the corrosive liquid; the structure is simple, the operation is convenient, and the manufacturing cost is low, and it can be reused, which greatly reduces the production cost.

Description

A wet etching device and using method thereof

technical field

The invention belongs to the field of semiconductor process equipment, and relates to a wet etching device and a using method thereof.

Background technique

In the manufacturing process of semiconductor integrated circuits and micro-electromechanical systems (MEMS), wet etching has always been a process for removing materials and has been widely used. With the development of integrated circuits and micro-electromechanical (MEMS) manufacturing processes, the traditional way of processing only on one side of the wafer can no longer meet the demand. Especially in MEMS process manufacturing, both sides of the wafer need to be processed, and the conditions of the process on both sides of the wafer are usually different. The graphic structure cannot be corroded and must be protected, so the technology of wafer single-side corrosion protection has emerged.

In the existing wafer single-sided etching technology, the wafer is generally immersed in a highly corrosive potassium hydroxide (KOH) solution or TMAH (Tetramethylammonium Hydroxide) solution for a long time at 80 ° C. The following methods are generally used to protect the front side of the wafer during the etching process:

1) One side of the wafer is protected with a corrosion fixture. However, the corrosion fixture needs to be pressed against the back of the wafer with a sealing ring, which will prevent the back pressed by the sealing ring from being corroded, and the corrosion of the entire back of the wafer cannot be realized; at the same time, the corrosion fixture needs to correspond to a wafer of a specific thickness, according to Wafers with different thicknesses need to use different types of etching fixtures, which is cumbersome; therefore, this method is limited in practical applications.

2) Coating a protective coating on the front side of the wafer to form protection for the front side of the wafer, as shown in FIG. 1 . As can be seen from FIG. 1, the protective coating 13 completely covers the front side of the wafer 11, but in some processes, the wafer 11 will have grooves 12. Therefore, using this method to treat the wafer 11 When protecting the front side of the surface, the applied protective coating 13 is easy to enter into the groove 12 . After the backside etching of the wafer 11 is completed, the protective coating 13 on the front side needs to be removed. If the protective coating 13 enters the groove 12, it is likely to be as shown in FIG. 2 . After removing the protective coating 13 on the front side of the wafer 11, a part of the remaining protective coating 13 remains in the trench 12, so that the filling is not correct in the subsequent trench filling process. Sufficient or even impossible to fill, thus affecting the performance of the device.

Furthermore, due to the limitations of the process, the thickness of the protective coating generally applied is relatively limited, and the thickness of the protective layer at the bottom of the hole or the side wall is limited, which cannot provide long-term protection. When the wafer is etched, if the groove The closed protective coating at the top of the opening is corroded, and the corrosion liquid or gas will enter into the groove, thereby easily causing damage to the groove of the wafer. At the same time, in the prior art, the general use as a protective coating, but The price is relatively expensive, and if there are high steps on the protected surface, It can't play a good protective role.

Contents of the invention

In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a wet etching device and its use method, which is used to solve the problem of using an etching fixture to etch the wafer when the wafer is etched on one side in the prior art. When protecting the protected surface or coating the protected surface of the wafer with a protective layer to protect the protected surface of the wafer, there is a problem that the entire corroded surface of the wafer cannot be corroded, and the corrosion protection layer used is easy to enter the wafer. In the groove, the performance of the device is affected, and the protective layer used is relatively expensive, which increases the production cost.

In order to achieve the above object and other related objects, the present invention provides a wet etching device, which is suitable for performing single-sided etching on a wafer, the wafer has a back side to be etched and a front side to be protected, and the wet etching device It includes: a base, a gasket and a vacuum generating device; a first airflow channel is arranged axially in the base, and the first airflow channel communicates with the upper surface of the base; the first airflow channel and the The vacuum generating device is connected; the liner is located on the upper surface of the base, and a groove is arranged in the liner, and the diameter of the bottom of the groove is greater than or equal to the diameter of the wafer; the groove A through-hole area is provided at the bottom of the tank, and the diameter of the through-hole area is smaller than the diameter of the wafer; a through-hole communicating with the first airflow channel is provided in the through-hole area, and the through-hole is connected to the first air flow channel. The above-mentioned first airflow channel corresponds up and down.

Preferably, the base includes a first sub-base and a second sub-base, the first airflow channel is located in the first sub-base; the first sub-base is also provided with the A cavity structure connected by the first air flow channel; a second air flow channel is arranged in the axial direction in the second sub-base, one end of the second air flow channel communicates with the cavity structure, and the other end communicates with the connected to the vacuum generator.

Preferably, the edge area of the front of the wafer is an arc-shaped area, the diameter of the bottom of the groove is equal to the diameter of the wafer, and the edge area of the bottom of the groove is an arc-shaped slope, and the arc-shaped The slope coincides with the arc-shaped area, so that when the wafer is at the bottom of the groove, the edge of the wafer and the edge of the bottom of the groove are completely attached together.

Preferably, the first airflow channels are evenly distributed in the base, and the through holes are evenly distributed in the bottom of the groove.

Preferably, the distance between two adjacent first airflow passages located in the middle area and the edge area of the base is smaller than the distance between two adjacent first airflow passages located in other areas of the base; The distance between two adjacent through holes in the middle area and the edge area of the pad is smaller than the distance between two adjacent through holes in other areas of the pad.

Preferably, the material of the base is tetrafluoroethylene, PP (Polypropylene, polypropylene) or Teflon.

Preferably, the gasket is made of silica gel or fluororubber.

Preferably, the gasket has the same shape and the same size as the first sub-base.

Preferably, the gasket has a circular cross-section, the first sub-base has a circular cross-section, and the groove bottom has a circular cross-section.

Preferably, the depth of the groove is greater than or equal to the thickness of the wafer.

Preferably, a filter valve is further provided between the base and the vacuum generating device, suitable for preventing corrosion liquid from entering the vacuum generating device.

The present invention also provides a method for using the above-mentioned wet etching device, comprising the following steps:

1) place the back side of a wafer to be etched upwards in the groove of the liner in the wet etching device, and make the edge of the wafer align with the edge of the groove; open the The vacuum generating device is used to adsorb the wafer at the bottom of the groove;

2) putting the pad with the wafer adsorbed thereon and the base into an etching solution, and etching the back side of the wafer to be etched;

3) After the etching is completed, the pad with the wafer adsorbed thereon and the base are taken out from the etching solution, and the wafer, the pad, and the base are rinsed with deionized water; the vacuum generating device is turned off, The wafer is removed from the pad.

Preferably, the etching solution used in step 2) is KOH solution or TMAH solution.

As mentioned above, the wet etching device of the present invention has the following beneficial effects:

1. The back side of the wafer to be etched is completely exposed, and the entire back side of the wafer can be etched.

2. The edge of the liner groove is provided with an arc-shaped slope that matches the arc-shaped area of the wafer edge, and the material of the liner is fluororubber or silica gel, both of which are stretchable , when the protected front side of the wafer is close to the bottom of the liner groove, under the action of the vacuum generating device, the liner can be deformed to the front side of the wafer through the deformation of the liner. The adsorption makes the entire front of the wafer closely adhere to the liner, prevents the corrosion solution from penetrating into the front of the wafer, and effectively protects the front of the wafer from contact with the corrosion solution.

3. The wet etching device is simple in structure, easy to operate, low in manufacturing cost, can be reused, and greatly reduces production cost.

Description of drawings

FIG. 1 shows a schematic cross-sectional view of a protective coating formed on the protected front side of a wafer in the prior art.

FIG. 2 is a schematic cross-sectional view after removing the protective coating on the protected front side of the wafer in the prior art.

FIG. 3 is a schematic structural view of the wet etching device of the present invention.

FIG. 4 is a schematic top view of the liner in the wet etching device of the present invention.

5 to 7 are partially enlarged schematic views of area A in FIG. 3 .

FIG. 8 is a schematic diagram of the structure of the wet etching device of the present invention after placing a wafer.

9 to 11 are partial enlarged schematic diagrams of area B in FIG. 8 .

Component designation description

11 wafers

12 grooves

13 Protective coating

20 base

201 First sub-pedestal

202 Second sub-base

21 Pads

22 Vacuum generator

23 First air flow channel

24 grooves

241 Via area

242 through holes

25 cavity structure

26 Second air flow channel

27 filter valve

28 wafers

29 connecting pipes

L ₁ Horizontal length of both ends of the arc slope

L ₂ Horizontal length of both ends of the arc area

h ₁ Height of arc slope

h ₂ the height of the arc area

detailed description

Embodiments of the present invention are described below through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes, and various modifications or changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present invention.

See Figures 3 through 11. It should be noted that the diagrams provided in this embodiment are only schematically illustrating the basic idea of the present invention, although only the components related to the present invention are shown in the diagrams rather than the number, shape and Dimensional drawing, the type, quantity and proportion of each component can be changed arbitrarily during actual implementation, and the component layout type may also be more complicated.

Please refer to FIG. 3 to FIG. 4 , FIG. 3 is a schematic structural diagram of a wet etching device, and FIG. 4 is a schematic top view of a pad in the wet etching device. The present invention provides a wet etching device, the wet etching device at least includes: a base 20, a liner 21 and a vacuum generating device 22; wherein, the base 20 is provided with a first gas flow channel 23 along the axial direction , the first airflow channel 23 communicates with the upper surface of the base 20; the first airflow channel 23 is connected to the vacuum generator 22; the gasket 21 is located on the upper surface of the base 20, The liner 21 is provided with a groove 24, the diameter of the bottom of the groove 24 is greater than or equal to the diameter of the wafer; the bottom of the groove 24 is provided with a through hole area 241, and the through hole area 241 The diameter is smaller than the diameter of the wafer, and the through hole area 241 is provided with a through hole 242 communicating with the first air flow channel 23 , and the through hole 242 corresponds to the first air flow channel 23 up and down.

Specifically, when using the wet etching device to etch the wafer, it is necessary to use a highly corrosive potassium hydroxide (KOH) solution or TMAH (Tetramethylammonium Hydroxide tetramethylammonium hydroxide) solution, therefore, in order to prevent The wet etching device is corroded by the potassium hydroxide solution or the TMAH solution, and the material of the base 20 and the substrate 21 can be all corrosion-resistant potassium hydroxide solution or TMAH solution in the prior art. one of the materials. Also, due to the need for the pad 21 on the upper surface of the base 20 and other process operations, the base 20 should have a certain hardness. Preferably, in this embodiment, the material of the base 20 is polytetrafluoroethylene, PP (Polypropylene, polypropylene) or Teflon (Polytetrafluoroethene, polytetrafluoroethylene). Preferably, in this embodiment, the material of the substrate 21 is silica gel or fluorine rubber. Due to the elasticity of silica gel and fluororubber, it can be deformed under the action of external force. The material of the substrate 21 is selected as silica gel or fluororubber that can be deformed, so that the wafer can be vacuumed under the action of the vacuum generating device 22. When being adsorbed at the bottom of the groove 24 , the deformation of the gasket 21 can complete the adsorption of the gasket 21 to the front side of the wafer, so that the wafer and the bottom of the groove 24 are more closely attached.

Specifically, the base 20 includes a first sub-base 201 and a second sub-base 202, the first airflow channel 23 is located in the first sub-base 201, and the first sub-base 201 A cavity structure 25 communicating with the first airflow passage 23 is also provided; a second airflow passage 26 is arranged axially in the second sub-base 202, and one end of the second airflow passage 26 is connected to the The cavity structure 25 is connected, and the other end is connected with the vacuum generating device 22 . The second air flow channel 26 can be connected with the vacuum generating device 22 through a connecting pipe 29 .

Specifically, the first airflow channels 23 may be evenly distributed in the base 20, and correspondingly, the through holes 242 may be evenly distributed in the bottom of the groove 24; the first airflow channels 23 The through holes 242 are evenly distributed, so that the force on the wafer is relatively uniform when it is adsorbed at the bottom of the groove 24 . Meanwhile, the first airflow channels 23 may also be non-uniformly distributed in the base 20 , and correspondingly, the through holes 242 may also be non-uniformly distributed at the bottom of the groove 24 . Preferably, in this embodiment, the distance between two adjacent first airflow passages 23 located in the middle area and the edge area of the base 20 is smaller than that between two adjacent first air channels 23 located in other areas of the base 20 . The distance between the airflow channels 23 : the distance between two adjacent through holes 242 located in the middle area and the edge area of the gasket 21 is smaller than the distance between two adjacent through holes 242 located in other areas of the gasket 21 . That is, in the middle area and the edge area of the base 20, the distribution of the first air flow channels 23 is denser than in other areas, and in the middle area and the edge area of the gasket 21, the through holes 242 The distribution is denser than in other regions. The distribution of the first airflow channels 23 in the middle area and the edge area of the base 20 is denser than that in other areas, and the distribution of the through holes 242 in the middle area and the edge area of the gasket 21 is It is denser than other areas, and when the wafer is adsorbed at the bottom of the groove 24, the central area and edge area of the wafer are subjected to greater force, so that the edge of the wafer is attached to the substrate 21 The tighter, more conducive to prevent the etching solution from contacting the front side of the wafer.

Specifically, the gasket 21 has the same shape and the same size as the first sub-base 201 . Preferably, the shape of the cross section of the pad 21 is the same as the shape of the cross section of the first sub-base 201 and the bottom of the groove, both of which are circular.

Specifically, a filter valve 27 is also provided between the base 20 and the vacuum generating device 22 to prevent the corrosive liquid accidentally entering the air flow channel in the base 20 from entering the vacuum when the vacuum generating device is working. The vacuum generating device 22 causes corrosion damage to the vacuum generating device 22 .

Please refer to FIG. 5 to FIG. 7 . FIG. 5 to FIG. 7 are enlarged schematic diagrams of area A in FIG. 3 . The bottom of the groove 24 may be a plane, and the sidewall of the groove 24 is also a plane, and the bottom of the groove 24 is vertically connected to the sidewall of the groove 24 , as shown in FIG. 5 . The edge of the bottom of the groove 24 can also be set as an arc slope as shown in Figure 6 and Figure 7, and the side wall of the groove 24 can be a plane as shown in Figure 6, or can be as shown in Figure 6 The curved slope shown in 7. Preferably, in this embodiment, the edge of the bottom of the groove 24 is set as an arc-shaped slope with a certain radian, and the sidewall of the groove 24 is also an arc-shaped slope with a certain radian. More preferably, the arc-shaped slope of the side wall of the groove 24 coincides with the upward extending surface of the arc-shaped slope of the bottom edge of the groove 24 . Since the edge of the wafer is arc-shaped with a certain radian, the edge of the bottom of the groove 24 is set as an arc-shaped slope with a certain radian, which can ensure that when the wafer is at the bottom of the groove 24, the wafer will The edge of the edge and the edge of the bottom of the groove 24 are completely and tightly fitted together.

Please refer to FIG. 8 . FIG. 8 is a schematic structural view of the wet etching device after the wafer is placed. As can be seen from FIG. 8 , after the wafer 28 is placed in the groove 24 , the vacuum generating device 22 starts to work, so that the wafer 28 is tightly adsorbed on the bottom of the groove 24 .

Specifically, the depth of the groove 24 should be greater than or equal to the thickness of the wafer 28 , preferably, in this embodiment, the depth of the groove 24 is greater than the thickness of the wafer 28 .

Please refer to FIG. 9 to FIG. 11 . FIG. 9 to FIG. 11 are enlarged schematic views of area B in FIG. 8 , wherein FIG. 9 corresponds to FIG. 5 , FIG. 10 corresponds to FIG. 6 , and FIG. 11 corresponds to FIG. 7 .

Please refer to FIG. 9 in conjunction with FIG. 5, the diameter of the wafer 28 is equal to the diameter of the bottom of the groove 24, the edge of the wafer 28 is flush with the edge of the groove 24, and the through hole 242 and The first air flow holes 23 are all located below the wafer 28, and when the wafer 28 is placed at the bottom of the groove 24, the wafer 28 covers all the through holes 242, that is, the wafer 28 The diameter of the wafer 28 is larger than the diameter of the through hole area 241 where the through holes 242 are distributed, so as to ensure that the wafer 28 can be tightly adsorbed on the bottom of the groove 24 when the vacuum generating device 22 is working. .

It should be noted that, at this time, the diameter of the wafer 28 may be smaller than the diameter of the bottom of the groove 24, as long as the diameter of the wafer 28 is greater than the diameter of the through hole region 241, so that the wafer 28 can completely cover the through hole 242 when placed at the bottom of the groove 24 .

Please refer to FIG. 10 in conjunction with FIG. 6, the diameter at the bottom of the groove 24 is equal to the diameter of the wafer 28, the edge area on the front side of the wafer 28 is an arc-shaped area, and the edge area at the bottom of the groove 24 is Arc-shaped slope, the arc-shaped slope coincides with the arc-shaped region, so that when the wafer 28 is at the bottom of the groove 24, the edge of the wafer 28 can be aligned with the groove 24 The edges of the bottom are completely and closely attached together, and when the wafer 28 is etched, the etching solution can be effectively prevented from contacting the front side of the wafer 28 .

Specifically, the arc-shaped slope at the bottom of the groove 24 coincides with the arc-shaped area of the edge of the wafer, that is, the horizontal length L1 _of the two ends of the arc-shaped slope is equal to the level of the two ends of the arc-shaped area. Length L ₂ , the height h ₁ of the arc-shaped slope is equal to the height h ₂ of the arc-shaped area, and the arc length of the longitudinal section of the arc-shaped slope is equal to the arc length of the longitudinal section of the arc-shaped area. Preferably, the horizontal length L1 _of both ends of the arc-shaped slope is 3-5 mm, that is, the distance between the end of the arc-shaped slope away from the side wall of the groove 24 and the edge of the wafer 28 is 3-5 mm. .

Specifically, the sidewall of the groove 24 is a vertical plane, and in the entire groove 24, only the area near the bottom and the sidewall is set as an arc-shaped slope.

As can be seen from FIG. 10 , by setting the edge of the groove 24 to have an arc-shaped slope matching the edge of the wafer 28 , when the wafer 28 is close to the bottom of the groove 24 , the edge of the wafer 28 can be close to the edge of the bottom of the groove 24, so that there is no gap between the wafer 28 and the bottom of the groove 24, effectively preventing the corrosion liquid from contacting the wafer. 28 protected frontal contacts.

Please refer to FIG. 10 in conjunction with FIG. 7, the diameter at the bottom of the groove 24 is equal to the diameter of the wafer 28, the edge area on the front side of the wafer 28 is an arc-shaped area, and the edge area at the bottom of the groove 24 is Arc-shaped slope, the arc-shaped slope coincides with the arc-shaped region, so that when the wafer 28 is at the bottom of the groove 24, the edge of the wafer 28 can be aligned with the groove 24 The edges of the bottom are completely and closely attached together, and when the wafer 28 is etched, the etching solution can be effectively prevented from contacting the front side of the wafer 28 .

Specifically, the arc-shaped slope at the bottom of the groove 24 coincides with the arc-shaped area of the edge of the wafer, that is, the horizontal length L1 _of the two ends of the arc-shaped slope is equal to the level of the two ends of the arc-shaped area. Length L ₂ , the height h ₁ of the arc-shaped slope is equal to the height h ₂ of the arc-shaped area, and the arc length of the longitudinal section of the arc-shaped slope is equal to the arc length of the longitudinal section of the arc-shaped area. Preferably, the horizontal length L1 _of both ends of the arc-shaped slope is 3-5 mm, that is, the distance between the end of the arc-shaped slope away from the side wall of the groove 24 and the edge of the wafer 28 is 3-5 mm. .

Specifically, the side wall of the groove 24 is also an arc-shaped slope. Preferably, in this embodiment, the arc-shaped slope of the side wall of the groove 24 and the arc-shaped slope at the bottom of the groove 24 The upward extension faces coincide.

Referring to FIGS. 5 to 7 , and FIGS. 9 to 11 , preferably, in this embodiment, the edge area at the bottom of the groove 24 is an arc-shaped slope matching the arc-shaped area of the edge of the wafer 28 , The side wall of the groove 24 is an arc-shaped slope coincident with an upwardly extending surface of the arc-shaped slope at the bottom of the groove 24 .

The present invention also provides a method for using the above-mentioned wet etching device, and the method for using includes the following steps:

1) provide a wet etching device, the diameter of the bottom of the groove of the wet etching device is the same as the diameter of the wafer to be etched; the back side of a wafer to be etched is placed in the wet etching device upwards In the groove of the pad, and make the edge of the wafer align with the edge of the groove; open the vacuum generating device, the wafer is adsorbed at the bottom of the groove;

2) Put the pad with the wafer adsorbed and the base into an etching solution, and etch the back side of the wafer to be etched; the etching solution used is potassium hydroxide (KOH) solution or TMAH (Tetram ethylammoniumHydroxide tetramethylammonium hydroxide) solution.

3) After the etching is completed, the pad with the wafer adsorbed thereon and the base are taken out from the etching solution, and the wafer, the pad, and the base are rinsed with deionized water; the vacuum generating device is turned off, The wafer is removed from the pad.

It should be noted that, the second gas flow passage in the second sub-base in the wet etching device is connected to the vacuum generating device through a connecting pipe, and when the connecting pipe is connected to the second air flow passage , the connection between the connecting pipe and the second gas flow channel should be sealed to avoid corrosion solution entering the second gas flow channel, which may cause corrosion damage to the protected front side of the wafer.

It should be further explained that, in the step 2) of etching the wafer, the end of the connecting pipe connected to the vacuum generating device and the vacuum generating device are kept out of the etching solution.

In summary, the present invention provides a wet etching device, the wet etching device includes a base, a liner and a vacuum generating device, the base is provided with an air flow channel communicating with the vacuum generating device , the substrate is provided with a groove, the bottom of the groove is provided with through holes communicating with the gas flow channel and corresponding one by one, and the edge of the bottom of the groove is provided with an arc area that matches the edge of the wafer. Curved slope. The wet etching device can completely expose the back side of the wafer to be etched, and can realize the etching of the entire back side of the wafer; The arc-shaped slope, and the material of the liner is fluororubber or silica gel, both of which are stretchable. When the protected front of the wafer is close to the bottom of the liner groove, Under the action of the vacuum generating device, the adsorption of the pad to the front of the wafer can be completed through the deformation of the pad, so that the entire front of the wafer is closely attached to the pad to prevent the corrosive liquid Penetrating into the front of the wafer, effectively protecting the front of the wafer from contact with the etching solution; the wet etching device is simple in structure, easy to operate, and low in manufacturing cost, can be reused, greatly reducing production cost.

The above-mentioned embodiments only illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed in the present invention shall still be covered by the claims of the present invention.

Claims (12)

1. a kind of wet etch processor, is suitable to carry out wafer single-sided corrosion, and the wafer has the back side to be corroded and needs The front of protection, it is characterised in that the wet etch processor includes：Pedestal, pad and vacuum generating device；

The first gas channel is provided with the pedestal vertically, first gas channel connects the upper surface of the pedestal；Institute The first gas channel is stated to be connected with the vacuum generating device；

The pad is provided with groove positioned at the upper surface of the pedestal in the pad, the bottom portion of groove with diameter greater than or Equal to the brilliant diameter of a circle；The bottom portion of groove is provided with via regions, and the diameter of the via regions is less than the wafer Diameter；The through hole being connected with first gas channel, the through hole and first air-flow are provided with the via regions Passage is corresponded to up and down；The fringe region of the wafer frontside is arc area, and the diameter of the bottom portion of groove is equal to the wafer Diameter, and the bottom portion of groove fringe region for arc it is domatic, the arc is domatic to match with the arc area, with During so that the wafer being located at the bottom portion of groove, the edge of the wafer is fitted in one completely with the edge of the bottom portion of groove Rise.

2. wet etch processor according to claim 1, it is characterised in that：The pedestal includes the first sub-base and second Sub-base, first gas channel is located in first sub-base；It is additionally provided with first sub-base and described first The cavity structure that gas channel is connected；The second gas channel, second air-flow are provided with vertically in second sub-base Passage end is connected with the cavity structure, and the other end is connected with the vacuum generating device.

3. wet etch processor according to claim 1, it is characterised in that：First gas channel is distributed evenly in In the pedestal, the through hole is distributed evenly in the bottom of the groove.

4. wet etch processor according to claim 1, it is characterised in that：Positioned at the pedestal zone line and marginal zone First gas described in be smaller than being located in other regions of the pedestal adjacent two of first gas channel described in adjacent the two of domain The spacing of circulation road；Positioned at the pad zone line and fringe region adjacent two described in through hole be smaller than be located at it is described Pad the spacing of through hole described in adjacent two in other regions.

5. wet etch processor according to claim 1, it is characterised in that：The material of the pedestal is tetrafluoroethene, gathers Propylene or Teflon.

6. wet etch processor according to claim 1, it is characterised in that：The material of the pad is silica gel or fluorine rubber Glue.

7. wet etch processor according to claim 1, it is characterised in that：The pad and the first sub-base shape Unanimously, size is identical.

8. wet etch processor according to claim 7, it is characterised in that：The pad cross section is shaped as circle, Being shaped as the first sub-base cross section be circular, the bottom portion of groove cross section is shaped as circle.

9. wet etch processor according to claim 1, it is characterised in that：The depth of the groove is more than or equal to described The thickness of wafer.

10. wet etch processor according to claim 1, it is characterised in that：The pedestal and the vacuum generating device Between be additionally provided with strainer valve, be suitable to prevent corrosive liquid from entering the vacuum generating device.

A kind of application method of 11. wet etch processors as any one of claim 1 to 10, it is characterised in that：Bag Include following steps：

1) in the groove of the pad that the back side to be corroded of a wafer is placed in the wet etch processor upward, and make described The edge of wafer aligns with the edge of the groove；The vacuum generating device is opened, by the wafer adsorption described recessed The bottom of groove；

2) pad for being adsorbed with wafer and the pedestal are put into etchant solution, the back side to be corroded to the wafer is entered Row corrosion；

3) after corrosion is finished, the pad for being adsorbed with wafer and the pedestal are taken out from etchant solution, uses deionization Water rinses the wafer, pad and pedestal；The vacuum generating device is closed, wafer is taken off from the pad.

The application method of 12. wet etch processors according to claim 11, it is characterised in that：Step 2) used in Etchant solution is KOH solution or TMAH solution.