CN114334608A

CN114334608A - Automatic photoresist stripping process

Info

Publication number: CN114334608A
Application number: CN202111487558.3A
Authority: CN
Inventors: 蒋磊; 陆瑞珠
Original assignee: Jiangsu Jinyuda Semiconductor Co ltd
Current assignee: Jiangsu Jinyuda Semiconductor Co ltd
Priority date: 2021-12-08
Filing date: 2021-12-08
Publication date: 2022-04-12

Abstract

The invention discloses an automatic photoresist stripping process, which comprises the following steps: s1, placing the first wafer box and the second wafer box on a wafer carrying table; s2, sending the wafers on the first wafer box into a flower basket one by one; s3, inclining the flower basket and descending the flower basket to soak in the stripping liquid; s4, lifting the flower basket, and placing the flower basket into the first wafer box piece by piece; s5, repeating the steps S2 to S4 to complete the soaking and photoresist removing of the wafer on the second wafer box; s6, in the whole process of soaking and removing the photoresist on the wafers on the second wafer box, all the wafers in the first wafer box are sent back to the first wafer box after rotary spraying and rotary cleaning are finished; s7, the first wafer box is removed and placed into a third wafer box, the wafers on the second wafer box are subjected to rotary spraying and rotary cleaning, and the wafers in the third wafer box are subjected to the steps S2 to S4. According to the photoresist removing and stripping process, the wafer is soaked for photoresist removing, sprayed for photoresist removing and cleaned, so that the photoresist removing efficiency and the photoresist removing quality are improved.

Description

Automatic photoresist stripping process

Technical Field

The invention relates to an automatic photoresist stripping process which is used for taking out photoresist and a metal layer from the surface of a wafer.

Background

In the field of semiconductor technology, a metal layer needs to be generated on the surface of a wafer, and the current common practice is to generate a layer of photoresist on the wafer, then etch the photoresist to form a line groove, then form a metal layer on the surface of the photoresist and the line groove of the wafer through a metal ion evaporation company, finally remove the useless photoresist and the metal layer through a photoresist removing and stripping process, and retain the metal in the line groove. The prior photoresist removing and stripping process is characterized in that a wafer is arranged on a rotary wafer clamping seat, the wafer clamping seat is positioned in a stripping cavity, then stripping liquid is sprayed on the surface of the wafer through a deflected spray head, and after the spraying and stripping are finished, the wafer is conveyed into a cleaning device by a wafer transfer arm for cleaning, however, the prior photoresist removing and stripping process has the following defects: 1. the photoresist is removed and stripped in a spraying mode, the photoresist is not completely removed, and the spraying and photoresist removing time is long; 2. the current spraying process is long in time, so that a large amount of stripping liquid is needed, and the waste of the stripping liquid is easily caused; 3. in the current spraying process, stripping liquid can be splashed to all places of a cleaning cavity, so that other parts inside the cleaning cavity are corroded.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the automatic photoresist removing and stripping process is characterized in that a wafer is subjected to soaking photoresist removing, spraying photoresist removing and cleaning, so that photoresist removing efficiency and photoresist removing quality are improved.

In order to solve the technical problems, the technical scheme of the invention is as follows: an automatic photoresist stripping process, comprising: s1, placing the first wafer box and the second wafer box, in which wafers without photoresist are placed, on a wafer carrying table; s2, conveying the wafers which are not subjected to photoresist removal on the first wafer box into a flower basket in the soaking, photoresist removal and stripping device piece by using the wafer transfer arm, and stopping placing after the flower basket is fully filled with the wafers; s3, inclining and descending the flower basket to soak in stripping liquid in a soaking cavity of the soaking, degumming and stripping device, completely soaking the flower basket in the stripping liquid, sealing the soaking cavity and exhausting air to an internal gas phase space; s4, after soaking, lifting the flower basket from the stripping liquid, adjusting the level of the flower basket, and placing the wafers into the first wafer box piece by using the wafer transfer arm; s5, repeating the steps S2 to S4, putting the wafers on the second wafer box into the flower basket by the wafer transfer arm, soaking the wafers in the stripping liquid, and putting the wafers into the second wafer box one by the wafer transfer arm after soaking is finished; s6, in the whole process that the wafers on the second wafer box are placed into a flower basket and the flower basket one by one for soaking and stripping, and the flower basket wafers are placed back into the second wafer box, all the wafers in the first wafer box are sent back into the first wafer box after rotary spraying and rotary cleaning are finished; wherein, the specific mode of rotatory spraying does: the wafer is sent into a wafer clamping seat of a spraying degumming stripping device, the wafer clamping seat rotates to drive the wafer to rotate, then a normal pressure nozzle and a lower nozzle are used for continuously spraying stripping liquid on the upper surface and the lower surface of the rotating wafer, after the normal pressure spraying time is finished, a high pressure nozzle is used for spraying the stripping liquid on the upper surface of the wafer at high pressure, the wafer is sent back into a first wafer box after the spraying is finished, and the step of rotary spraying of one wafer is finished; s7, the first wafer box is removed and placed into a third wafer box, the wafers on the second wafer box are subjected to rotary spraying and rotary cleaning, and the wafers in the third wafer box are subjected to the steps S2 to S4, and the steps are alternated.

As a preferable scheme, the spin cleaning manner in step S6 is:

s61, putting the wafer into a wafer cassette of the cleaning device;

s62, the wafer cassette drives the wafer to rotate;

s63, spraying pure water to clean the upper and lower surfaces of the wafer by using the high-pressure nozzles and part of the lower nozzles, after cleaning, spraying nitrogen to the upper and lower surfaces of the wafer by using the normal-pressure nozzles and the rest of the lower nozzles to dry the upper and lower surfaces of the wafer, and blowing the stripping liquid to dry the wafer by using the high-pressure nozzles to spray pure water in the rotary cleaning process.

Preferably, the rotation center of the wafer cassette is not concentric with the center of the wafer, so that all liquid on the wafer can be thrown out.

Preferably, the flower basket is inclined at an angle of 30-45 degrees.

Preferably, the time for soaking the flower basket in the stripping liquid is not less than 5 minutes.

As a preferable scheme, in the step S6, the normal pressure spray nozzle and the lower nozzle use the recovered stripping liquid, the high pressure nozzle uses the new stripping liquid, the recovered stripping liquid can be used during the normal pressure spray, even some impurities in the recovered stripping liquid will not damage the surface of the wafer because of small spraying impact force, and the new liquid spray nozzle is used during the high pressure spray, so that the pressure is high, the washing is easier, the quality of the sprayed photoresist is ensured, and the stripping liquid is reused, thereby reducing the consumption of the stripping liquid.

As a preferable scheme, in the process of the normal pressure spraying and the high pressure spraying of the wafer in the step S6, the wafer cassette is covered and protected by the protective cover, so that the stripping liquid can be effectively protected.

As a preferred scheme, the protective housing comprises an outer fixed ring and an inner fixed ring which are positioned on the periphery of the wafer clamping seat, and a movable housing which can lift and is positioned between the outer fixed ring and the inner fixed ring, when a wafer enters the wafer clamping seat, the movable housing descends to enable the wafer clamping seat to be exposed from a spraying window on the movable housing, when spraying and removing glue, the movable housing ascends to protect the wafer clamping seat, the lower end of the movable housing is always positioned in the range of the outer fixed ring and the inner fixed ring, the material can be conveniently fed and discharged through the lifting action of the movable housing, meanwhile, in the spraying process, the movable housing protects the wafer, and the lower end of the movable housing is always positioned in the range of the outer fixed ring and the inner fixed ring, so that a reversed-square protective structure is formed, and the protective effect is better.

After the technical scheme is adopted, the invention has the effects that: compared with the prior art, the automatic photoresist stripping process has the following advantages:

1. the process combines soaking degumming and spraying degumming, so that the degumming is more thorough;

2. in the soaking and photoresist removing process of the process, a plurality of wafers can be washed and soaked at one time by utilizing the flower basket, the flower basket is obliquely lifted and soaked in stripping liquid, and the wafers are uniformly inclined towards one side due to the inclination of the flower basket, when the wafer enters the stripping liquid, the position of the wafer may be changed due to the influence of buoyancy, but because the wafer inclines, the wafer still inclines to the same side under the action of gravity, and finally depends on the side wall of the flower basket, meanwhile, the contact between the stripping liquid and the adhesive layer can be better facilitated due to the inclination of the wafer during the photoresist stripping, especially the photoresist on the wafer can be separated and fall off at an accelerated speed due to the inclination, after the flower basket lifts the stripping liquid, the flower basket is adjusted to be horizontal, so that the positions of all wafers on the flower basket are uniform, thereby facilitating the accurate moving of the wafer transfer arm and sending the wafer to the first wafer box and the second wafer box;

3. the process has higher photoresist removing efficiency, wafers are put into a flower basket one by one to be soaked, the wafers can be sprayed to remove photoresist and cleaned in the soaking process, particularly, the spraying and photoresist removing time is shortened after the soaking and photoresist removing are carried out, so that the spraying and cleaning of all wafers in another wafer box can be finished in the whole process flow time (total time of loading, soaking and unloading) of the soaking and photoresist removing, and the process beat is more compact;

4. the spraying in the process adopts a mode of combining high-pressure spraying and normal-pressure spraying, and the photoresist and the useless metal layer on the upper surface of the wafer can be removed more quickly and effectively.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is a perspective view of the structure of an embodiment of the present invention;

FIG. 2 is a perspective view with the housing hidden;

FIG. 3 is a partial perspective view of the immersion stripping apparatus;

FIG. 4 is a partial perspective cross-sectional view of the immersion stripping apparatus;

FIG. 5 is a perspective view of a spray stripping apparatus;

FIG. 6 is a perspective view of the spray stripping device with the hidden upper cover of the outer chamber;

FIG. 7 is a top view of the upper cover of the outer chamber body hidden;

FIG. 8 is a cross-sectional view at A-A of FIG. 7;

FIG. 9 is a perspective view of the outer chamber upper cover and movable closure hidden;

in the drawings: 1. a frame; 2. soaking, degumming and stripping devices 2; 201. soaking the base; 202. operating a window; 203. soaking the base; 204. soaking the lifting seat; 205. soaking the mounting seat; 206. soaking the mounting plate; 207. a flower basket 207; 208. a liquid inlet pipe; 209. a heating device; 210. an upper cavity; 211. a lower cavity; 212. a bin gate; 213. an opening and closing power device; 214. a door frame; 215. installing an embedding groove; 216. a first suspension bar; 217. a second suspension bar; 218. a rodless electric cylinder; 219. soaking the connecting seat; 220. soaking the connecting sleeve; 221. a cylindrical threaded sleeve; 222. mounting grooves; 223. an electric cylinder support; 224. horizontally installing strip holes; 225. avoiding holes; 226. a liquid level meter; 227. a temperature sensor; 3. a slide stage; 4. spraying a photoresist removing and stripping device; 401. an outer cavity; 4011. a feed inlet; 4012. an upper cover; 4013. an air extraction opening; 4014. a middle ring groove; 4015. an inner ring groove; 402. a cleaning chamber; 4021. a housing body; 4022. spraying a window; 4023. an annular caulking groove; 4024. an outer casing; 4025. an outer retainer ring 4025; 4026. an inner retainer ring 4026; 403. a wafer cassette 403; 4031. installing a base; 4032. a rotary power device; 4033. a card seat body; 404. a second lifting swing arm; 405. a first lifting swing arm; 406. a feed inlet plugging device; 4061. a plugging plate; 4062. plugging the air cylinder; 407. an outer drain port; 408. an angle adjusting mechanism; 4081. fixing a bracket; 4082. adjusting the bracket; 4083. adjusting the bar holes; 409. a lifting connecting rod; 410. a first lifting power device; 411. a middle liquid discharge port; 412. an inner drainage port; 5. a cleaning device; 6. a wafer cassette; 7. a wafer transfer arm.

Detailed Description

The present invention is described in further detail below with reference to specific examples.

An automatic photoresist stripping process, comprising: s1, placing the first wafer box and the second wafer box, in which wafers without photoresist are placed, on a wafer carrying table; the first wafer cassette and the second wafer cassette are alternated, and when one of the wafer cassettes is stripped, a new wafer cassette is replaced.

S2, the wafer transfer arm 7 is used for sending the wafers which are not subjected to photoresist removal on the first wafer box into the flower basket 207 in the soaking, photoresist removal and stripping device 2 piece by piece, and the placing is stopped after the flower basket 207 is fully filled with the wafers;

s3, inclining and descending the flower basket 207 to be soaked in stripping liquid in a soaking cavity of the soaking and degumming stripping device 2, wherein the inclination angle of the flower basket 207 is 30-45 degrees, the time for completely soaking the flower basket 207 in the stripping liquid is not less than 5 minutes, and sealing the soaking cavity and exhausting air to an internal gas phase space;

s4, after soaking, lifting the flower basket 207 out of the stripping liquid, adjusting the level of the flower basket 207, and placing the wafers into the first wafer box piece by using the wafer transfer arm 7;

s5, repeating the steps S2 to S4, putting the wafers on the second wafer box into the flower basket 207 by the wafer transfer arm 7, soaking the wafers in the stripping liquid, and putting the wafers into the second wafer box one by the wafer transfer arm 7 after soaking;

s6, putting the wafers on the second wafer box into the flower basket 207, soaking and peeling the wafers in the flower basket 207 and putting the wafers in the flower basket 207 back into the second wafer box one by one, wherein all the wafers in the first wafer box are sent back into the first wafer box after rotary spraying and rotary cleaning are finished; wherein, the specific mode of rotatory spraying does: the wafer is sent into a wafer clamping seat 403 of a spraying degumming stripping device 4, the wafer clamping seat 403 rotates to drive the wafer to rotate, then a normal pressure nozzle and a lower nozzle are used for continuously spraying stripping liquid on the upper surface and the lower surface of the rotating wafer, after the normal pressure spraying time is over, a high pressure nozzle is used for spraying the stripping liquid on the upper surface of the wafer at high pressure, the wafer is sent back to a first wafer box after the spraying is finished, and the step of rotary spraying of one wafer is finished; the center of rotation of the wafer chuck 403 is not concentric with the center of the wafer, so that the wafer rotates eccentrically and the liquid thereon is thrown off.

S7, the first wafer box is removed and placed into a third wafer box, the wafers on the second wafer box are subjected to rotary spraying and rotary cleaning, and the wafers in the third wafer box are subjected to the steps S2 to S4, and the steps are alternated.

The manner of the rotary cleaning in step S6 is as follows:

s61, putting the wafer into the wafer cassette 403 of the cleaning device 5;

s62, the wafer cassette 403 drives the wafer to rotate;

In the step S6, the normal pressure spray middle nozzle and the normal pressure spray lower nozzle use the recovered stripping liquid, the high pressure spray nozzle uses the new stripping liquid, and in the step S6, the wafer cassette 403 is covered and buckled by the protective cover in the normal pressure spray and high pressure spray processes, so that the stripping liquid can be effectively protected. The protective housing comprises an outer fixing ring 4025 and an inner fixing ring 4026 which are positioned on the periphery of the wafer cassette 403, and a movable housing which can lift and is positioned between the outer fixing ring 4025 and the inner fixing ring 4026, when a wafer enters the wafer cassette 403, the movable housing descends to expose the wafer cassette 403 from a spraying window on the movable housing, when spraying and removing glue, the movable housing ascends to protect the wafer cassette 403, the lower end of the movable housing is always positioned in the range of the outer fixing ring 4025 and the inner fixing ring 4026, the material can be conveniently fed and discharged through the lifting action of the movable housing, meanwhile, in the spraying process, the movable housing protects the wafer, the lower end of the movable housing is always positioned in the range of the outer fixing ring 4025 and the inner fixing ring 4026, a zigzag protective structure is formed, and the protective effect is better.

In addition, the invention also discloses equipment for realizing the automatic photoresist stripping process, and as shown in fig. 1 to 9, the automatic photoresist stripping machine comprises a frame 1; the frame 1 is a frame structure made of aluminum profiles.

The wafer carrying platform 3 is used for placing wafer boxes 6, two wafer boxes 6 are placed on the wafer carrying platform 3, wafers which are not stripped by photoresist are placed on one wafer box 6, and wafers which are stripped by photoresist are placed on the other wafer box 6.

The spray degumming stripping device 4 installed on the frame 1 is shown in fig. 5 to 9, the spray degumming stripping device 4 comprises an outer cavity 401, the upper end of the outer cavity 401 is hinged with an openable upper cover 4012, a stripping cavity is installed in the outer cavity 401, a wafer cassette 403 for clamping a wafer is rotatably installed in the stripping cavity, and the wafer cassette 403 is driven by a rotary power device 4032.

Wherein the wafer chuck 403 comprises a mounting base 4031 detachably fixed at the bottom of the outer cavity 401 and located in the inner retaining ring 4026, the mounting base 4031 is rotatably mounted with a chuck body 4033, wherein the chuck body 4033 is of a conventional structure at present, a chuck plate for conveniently positioning a wafer is arranged on the chuck body 4033, the chuck plate is composed of a plurality of support pillars, each support pillar is provided with a support step, the wafer is placed on the support step and positioned by the support pillar, the wafer is driven to rotate together when rotating, the rotary power device 4032 is fixed below the outer cavity 401, a power end of the rotary power device 4032 is fixed with the chuck body 4033, the lower nozzle is mounted on the mounting base 4031 through an angle adjusting mechanism 408, the center of the spray window 4022 is concentric with the center of the chuck plate, wherein the rotary power device 4032 is a driving motor, an output shaft of the driving motor is connected with the cassette body 4033 to drive the cassette body 4033 to rotate.

Wherein, angle adjustment mechanism 408 is including being fixed in the fixed bolster 4081 that just the slope set up on installation base 4031, set up the regulation strip hole 4083 of slope on the fixed bolster 4081, a radial minute direction has in the extending direction of regulation strip hole 4083, install locking bolt in the regulation strip hole 4083, locking bolt connection has regulation support 4082, the nozzle is fixed in down on the regulation support 4082, just can change regulation support 4082 angle through loosening locking bolt to regulation support 4082 can slide in the within range of regulation strip hole 4083, not only changes the angle of nozzle down, can change the position of spraying moreover, thereby changes injection pressure, and the effect of cleaing away at the wafer back is also better like this.

The stripping cavity comprises an outer fixing ring 4025, an inner fixing ring 4026 and a movable housing, the wafer cassette 403 is positioned in the inner fixing ring 4026, the outer fixing ring 4025 and the inner fixing ring 4026 are fixed at the bottom of the outer cavity 401, the movable housing is installed on the outer cavity 401 in a lifting mode and is positioned between the outer fixing ring 4025 and the inner fixing ring 4026, a spraying window 4022 is arranged at the upper end of the movable housing, the movable housing is driven by a second lifting power device, and when the movable housing is positioned at a lower dead point, the wafer cassette 403 is exposed out of the spraying window 4022. A first lifting swing arm 405 and a second lifting swing arm 404 are arranged on the outer side of the stripping cavity in the outer cavity 401, a normal pressure nozzle and a high pressure nozzle are respectively installed at the tail ends of the first lifting swing arm 405 and the second lifting swing arm 404, a lower nozzle for spraying the bottom surface of the wafer is also installed in the stripping cavity, the lower nozzle, the normal pressure nozzle and the high pressure nozzle are respectively communicated with a stripping liquid supply system, an outer liquid discharge port 407 is arranged at the outer side of the stripping cavity at the bottom of the outer cavity 401, a middle liquid discharge port 411 is arranged between an outer fixing ring 4025 and an inner fixing ring 4026 at the bottom of the outer cavity 401, an inner liquid discharge port 412 is arranged in the inner fixing ring 4026 at the bottom of the outer cavity 401, the outer liquid discharge port 407, the middle liquid discharge port 411 and the inner liquid discharge port 412 are all communicated with a waste liquid collecting system pipeline, an air suction port 4013 and a feed port 4011 are also arranged on the outer cavity 401, and a feed port plugging device 406 is installed at the feed port 4011, the feed inlet plugging device 406 comprises a plugging plate 4061 which is slidably mounted at the feed inlet 4011 and driven by a plugging cylinder 4062, the pumping port 4013 is communicated with a pumping system, and the spray photoresist stripping device 4 can better strip photoresist, reduce consumption of stripping liquid and reduce splashing of the stripping liquid.

In this embodiment, the movable housing includes a housing body 4021, the spraying window 4022 is disposed in the middle of the upper end of the housing body 4021, the housing body 4021 is installed on the outer cavity 401 through a lifting structure, the lower end of the housing body 4021 is provided with an annular caulking groove 4023, and the inner fixing ring 4026 is located in the annular caulking groove 4023. The movable cover casing is reasonable in structure, the inner fixing ring 4026 can be further protected by the annular caulking groove 4023, two protective barriers are formed, and stripping liquid is further prevented from being splashed out of the cleaning cavity 402. The lifting structure comprises a plurality of lifting connecting rods 409, the upper ends of the lifting connecting rods 409 extend into the annular caulking groove 4023 and are fixed with the housing body 4021, a mounting ring is fixed at the upper end of each lifting connecting rod 409, and the mounting ring is clamped or connected in the annular caulking groove 4023 through a bolt, so that the lifting connecting rods 409 and the housing body 4021 are fixed.

The lower end of the lifting connecting rod 409 penetrates through the bottom of the inner fixing ring 4026 and the bottom of the outer cavity 401 in a sliding mode, the lower end of the lifting connecting rod 409 is connected with the second lifting power device, the second lifting power device adopts a cylinder, an outer housing 4024 is further arranged outside the housing body 4021, an annular space is formed between the outer housing 4024 and the housing body 4021, the lower end of the outer housing 4024 is located between the outer fixing ring 4025 and the inner fixing ring 4026, and the lower end of the outer housing 4024 is lower than the lower end of the housing body 4021. Middle leakage fluid dram 411 and interior leakage fluid dram 412's quantity is a plurality of and become the circumference and arrange, be provided with respectively on the bottom of outer cavity 401 with middle leakage fluid dram 411 and interior leakage fluid dram 412 position corresponding middle annular 4014 and inner ring groove 4015, utilize middle annular 4014 and inner ring groove 4015 to collect stripping liquid like this, conveniently discharge from middle leakage fluid dram 411 and interior leakage fluid dram 412.

In this embodiment, the stripping solution supply system includes a new solution storage tank and a recovered solution storage tank, the new solution storage tank is communicated with the high-pressure nozzle through the new solution supply system, and the recovered solution storage tank is communicated with the lower nozzle and the normal-pressure nozzle through the recovered solution supply system; the waste liquid collecting system is communicated with the recovery liquid storage tank through the recovery liquid supplementing pipeline, the filter is arranged on the recovery liquid supplementing pipeline, so that the recovery liquid can be adopted for spraying when spraying at normal pressure, the concentration of the recovered stripping liquid is relatively low, solid particles are removed after filtering through the filter, after the spraying is carried out for a period of time, most of photoresist is removed at the moment, metal lines on the surface of a wafer are partially exposed or completely exposed, high-pressure new liquid is recycled for spraying and stripping at the moment, and therefore good stripping and stripping effects are guaranteed, and consumption of the stripping liquid is reduced.

As shown in fig. 3 and 4, the soaking and stripping device 2 mounted on the frame 1 is used for soaking the wafer in the stripping solution to strip the photoresist; the soaking, degumming and stripping device 2 comprises a soaking base 201, a soaking cavity is arranged on the soaking base 201, an operation window 202 which is convenient for the wafer transfer arm 7 to feed and discharge is arranged on the soaking cavity, a soaking base 203 is arranged outside the soaking cavity on the soaking base 201, a soaking lifting base 204 is vertically lifted on the soaking base 203, the soaking lifting base 204 is driven by a first lifting power device 410, a soaking mounting base 205 is arranged on the soaking lifting base 204, the soaking mounting base 205 is provided with a soaking mounting plate 206 above the soaking cavity, a hanging and adjusting device for hanging and adjusting the angle of a flower basket 207 is arranged on the soaking mounting plate 206, the lower end of the hanging and adjusting device extends into the flower basket 207 in the soaking cavity, a liquid inlet pipe 208 communicated with a stripping liquid supply system is arranged on the soaking cavity, be provided with the heating device 209 that is used for heating the stripping liquid in the soaking cavity, the position movable mounting that lies in operation window 202 on the soaking cavity has door 212, be provided with the drive on the soaking cavity the switching power device 213 that door 212 closed or opened.

When the device is used, firstly, stripping liquid is introduced into the soaking cavity by using the liquid inlet pipe 208, the device is heated by using the heating device 209, the temperature of the stripping liquid meets the requirement of a photoresist stripping process, wafers are conveyed into the flower basket 207 from the operation window 202 by using the wafer transfer arm 7, the flower basket 207 suspended by the suspension adjusting device is in a horizontal state at the moment, the wafers can conveniently enter, when one wafer is placed into each wafer placing groove on the flower basket 207, the lifting seat moves downwards by the height of one wafer placing groove, the empty wafer placing grooves are aligned to the operation window 202, the flower basket 207 is inclined by the suspension adjusting device after all the wafer placing grooves are placed with the wafers, then the flower basket 207 is driven by the first lifting power device 410 to be immersed into the stripping liquid for photoresist stripping, the wafers are uniformly inclined towards one side due to the inclination of the flower basket 207, and when the wafers enter the stripping liquid, the positions of the wafers can possibly change due to the influence of buoyancy, however, the wafer is inclined, so that the wafer still tends to be on the same side under the action of gravity and finally depends on the side wall of the basket 207, and meanwhile, the wafer is inclined during photoresist removing, so that the stripping liquid can be better conveniently contacted with the adhesive layer, especially, the photoresist on the wafer can be separated and fall off at an accelerated speed due to the inclination, and after the wafer is lifted to be separated from the stripping liquid, the suspension adjusting device can adjust the angle to enable the wafer to be horizontal, so that the wafer can be conveniently moved out.

As shown in fig. 4, the soaking cavity includes an upper cavity 210 and a lower cavity 211 fixed to each other, the operation window 202 is disposed on the upper cavity 210, the liquid inlet pipe 208 and the heating device 209 are disposed on the lower cavity 211, a door 212 is movably mounted on the upper cavity 210 at the operation window 202, an opening and closing power device 213 for driving the door 212 to close or open is disposed on the upper cavity 210, the operation window 202 is disposed on a side wall of the upper cavity 210, a rectangular door frame 214 is fixed on an opening edge of the operation window 202, an upper end opening of the door frame 214 is provided with a mounting embedded groove 215, the door 212 is slidably mounted in the mounting embedded groove 215, the opening and closing power device 213 drives the door 212 to vertically slide in the mounting embedded groove 215, an exhaust port is disposed on the upper cavity 210 and is communicated with the exhaust pipe, and a liquid level meter 226 and a temperature sensor 227 are further disposed on the lower cavity 211.

The suspension adjusting device comprises a first suspension rod 216 and a second suspension rod 217 which are parallel, the upper end of the first suspension rod 216 is fixed on the soaking mounting plate 206, the lower end of the first suspension rod 216 is hinged to one side of the upper end of the flower basket 207, the second suspension rod 217 is axially and slidably mounted on the soaking mounting plate 206 and driven by an axial power device, and the lower end of the second suspension rod 217 is hinged to the other side of the upper end of the flower basket 207.

Wherein, the axial power device comprises a rodless electric cylinder 218 fixed on the soaking mounting plate 206, the sliding direction of the sliding part of the rodless electric cylinder 218 is vertical, the power end of the rodless electric cylinder 218 is connected with the upper end of the second suspension rod 217 through a soaking connection seat 219, the soaking connection seat 219 comprises an L-shaped soaking connection plate, one plate part of the soaking connection plate is fixed on the sliding part of the rodless electric cylinder 218 through a bolt, the lower end of the other plate part of the soaking connection plate is connected with a soaking connection sleeve 220 through a bolt, a cylindrical screw sleeve 221 is in threaded connection with the soaking connection sleeve 220, the upper end of the second suspension rod 217 is provided with a spherical head part, a spherical inner hole convenient for the connection of the spherical head part is arranged on the cylindrical screw sleeve 221, the spherical head part is arranged in the spherical inner hole of the cylindrical screw sleeve 221, and the second suspension rod 217 can be better driven by the spherical head part and the spherical inner hole, the cooperation of the ball head portion and the spherical inner hole can facilitate the second suspension rod 217 to lift better and more stably, and even if some assembly errors exist, the second suspension rod 217 can move smoothly.

Soaking and being provided with a mounting groove 222 on the mounting panel 206, rodless electric jar 218 is fixed on the electric jar support 223 of an L shape, fix in mounting groove 222 through fixing bolt on the electric jar support 223, be provided with horizontal installation slotted hole 224 on the electric jar support 223, the extension of horizontal installation slotted hole 224 is to first suspension rod 216, fixing bolt retrains in horizontal installation slotted hole 224, it is convenient to be provided with on the mounting panel 206 to soak the hole 225 that dodges that the connecting seat goes up and down, adopt foretell structure, the mounted position of rodless electric jar 218 can be adjusted to the convenience is connected with second suspension rod 217.

A cleaning device 5 arranged on the frame 1 and used for cleaning the upper surface and the lower surface of the wafer; the structure of the cleaning device 5 and the spray stripping device 4 is the same in this embodiment, the high-pressure nozzle and part of the lower nozzles of the cleaning device 5 are communicated with the pure water supply system, the normal-pressure nozzle and the rest of the lower nozzles of the cleaning device 5 are communicated with the nitrogen supply system, so that the wafer which is soaked for stripping and sprayed for stripping is sent into the cleaning device 5, then the high-pressure nozzle and part of the lower nozzles are utilized for upper and lower spray cleaning, and after the cleaning is completed, the normal-pressure nozzle and the rest of the lower nozzles are utilized for nitrogen purging, so that the moisture on the surface is taken out, and the cleaning work of the wafer is completed.

And the wafer transfer arm 7 is arranged on the rack 1 and used for transplanting wafers, and the slide holder 3, the spraying and degumming stripping device 4, the soaking and degumming stripping device 2 and the cleaning device 5 are respectively positioned at the periphery of the wafer transfer arm 7. The wafer transfer arm 7 is a conventional transfer arm in the semiconductor production industry, and the transfer arm can deflect and lift, and the wafer is sucked to move to a specified position by using a vacuum adsorption mode.

The above-mentioned embodiments are merely descriptions of the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention, and various modifications and alterations made to the technical solution of the present invention without departing from the spirit of the present invention are intended to fall within the scope of the present invention defined by the claims.

Claims

1. An automatic photoresist stripping process is characterized in that: the method comprises the following steps:

s1, placing the first wafer box and the second wafer box, in which wafers without photoresist are placed, on a wafer carrying table;

s2, conveying the wafers which are not subjected to photoresist removal on the first wafer box into a flower basket in the soaking, photoresist removal and stripping device piece by using the wafer transfer arm, and stopping placing after the flower basket is fully filled with the wafers;

s3, inclining and descending the flower basket to soak in stripping liquid in a soaking cavity of the soaking, degumming and stripping device, completely soaking the flower basket in the stripping liquid, sealing the soaking cavity and exhausting air to an internal gas phase space;

s4, after soaking, lifting the flower basket from the stripping liquid, adjusting the level of the flower basket, and placing the wafers into the first wafer box piece by using the wafer transfer arm;

s5, repeating the steps S2 to S4, putting the wafers on the second wafer box into the flower basket by the wafer transfer arm, soaking the wafers in the stripping liquid, and putting the wafers into the second wafer box one by the wafer transfer arm after soaking is finished;

s6, in the whole process that the wafers on the second wafer box are placed into a flower basket and the flower basket one by one for soaking and stripping, and the flower basket wafers are placed back into the second wafer box, all the wafers in the first wafer box are sent back into the first wafer box after rotary spraying and rotary cleaning are finished;

wherein, the specific mode of rotatory spraying does: the wafer is sent into a wafer clamping seat of a spraying degumming stripping device, the wafer clamping seat rotates to drive the wafer to rotate, then a normal pressure nozzle and a lower nozzle are used for continuously spraying stripping liquid on the upper surface and the lower surface of the rotating wafer, after the normal pressure spraying time is finished, a high pressure nozzle is used for spraying the stripping liquid on the upper surface of the wafer at high pressure, the wafer is sent back into a first wafer box after the spraying is finished, and the step of rotary spraying of one wafer is finished;

2. The automatic photoresist stripping process of claim 1, wherein: the manner of the rotary cleaning in step S6 is as follows:

s61, putting the wafer into a wafer cassette of the cleaning device;

s62, the wafer cassette drives the wafer to rotate;

and S63, spraying pure water to clean the upper and lower surfaces of the wafer by using the high-pressure nozzles and part of the lower nozzles, and after cleaning is finished, spraying nitrogen to the upper and lower surfaces of the wafer by using the normal-pressure nozzles and the rest of the lower nozzles to dry the upper and lower surfaces of the wafer.

3. The automatic photoresist stripping process of claim 2, wherein: the rotation center of the wafer clamping seat is not concentric with the center of the wafer.

4. The automatic photoresist stripping process of claim 3, wherein: the inclination angle of the flower basket is 30-45 degrees.

5. The automatic photoresist stripping process of claim 4, wherein: the time for soaking the flower basket in the stripping liquid is not less than 5 minutes.

6. The automatic photoresist stripping process of claim 5, wherein: in the step S6, the middle and lower nozzles are sprayed under normal pressure to use the recovered stripping liquid, and the high-pressure nozzle uses the new stripping liquid.

7. The automatic photoresist stripping process of claim 6, wherein: and in the step S6, the wafer cassette is covered and buckled by a protective cover in the processes of normal pressure spraying and high pressure spraying of the wafer.

8. The automatic photoresist stripping process of claim 7, wherein: the protective housing comprises an outer fixing ring and an inner fixing ring which are arranged on the periphery of the wafer clamping seat and a movable housing which is arranged between the outer fixing ring and the inner fixing ring and can lift, when a wafer enters the wafer clamping seat, the movable housing descends to enable the wafer clamping seat to be exposed from a spraying window on the movable housing, when spraying and removing glue, the movable housing ascends to protect the wafer clamping seat, and the lower end of the movable housing is always located in the range of the outer fixing ring and the inner fixing ring.