A wafer wet processing equipment and a wafer wet processing method

Abstract

This invention relates to the field of semiconductor manufacturing and discloses a wafer wet processing apparatus, comprising: a rotatable chuck having an inner cavity, the inner cavity being divided into an upper cavity and a lower cavity according to the wafer placement position; a first processing liquid nozzle, a second processing liquid nozzle, and a surface tension reducing liquid nozzle, for supplying a first processing liquid, a second processing liquid, and a surface tension reducing liquid to the central region of the upper cavity, respectively; a first heating device for heating a first region surrounding the central region of the lower cavity; a second heating device for heating a second region surrounding the first region; a first processing liquid conduit and a second processing liquid conduit for supplying the first processing liquid and the second processing liquid to the central region of the lower cavity; and a first temperature-regulating gas channel within the rotatable chuck for supplying adjusting gas to the central region of the lower cavity. The technical solution provided by this invention can avoid condensation defects during the wafer wet processing process.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing, and more specifically to wafer wet processing equipment and wafer wet processing methods. Background Technology

[0002] During the wet processing of wafers, various processing solutions and surface tension reducing solutions are added to clean and dry the wafer surface. During the evaporation of the surface tension reducing solution, the temperature of the wafer surface will drop due to the latent heat of phase transition of the surface tension reducing solution. Gas impurities around the wafer may condense and be adsorbed onto the wafer surface, forming condensation defects.

[0003] The aforementioned defects are highly likely to remain even after the cleaning process, significantly impacting the yield rate. Current methods to address this condensation defect primarily involve extending the cleaning time to reduce impurity gases, or introducing clean, dry gas during the evaporation of the treatment liquid to reduce condensation of impurity gases. However, existing methods cannot completely eliminate condensation defects, making the more effective solution a pressing technical problem for those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to overcome the problem of condensation defects in the existing wafer wet processing technology, and to provide a wafer wet processing equipment and method. During the evaporation of the surface tension reducing liquid, the lower surface of the wafer is heated and the wafer surface is kept at a high temperature until the surface tension reducing liquid is completely evaporated. This prevents impurity gases in the equipment from being adsorbed due to the high temperature of the wafer surface, thereby avoiding condensation defects.

[0005] To achieve the above objectives, one embodiment of the present invention provides a wafer wet processing apparatus, comprising:

[0006] A rotatable chuck having an inner cavity for placing a wafer, the inner cavity being divided into an upper cavity and a lower cavity according to the placement position of the wafer;

[0007] The first treatment fluid nozzle, the second treatment fluid nozzle, and the surface tension reducing fluid nozzle are respectively disposed above the rotatable chuck, and are used to supply the first treatment fluid, the second treatment fluid, and the surface tension reducing fluid to the central area of ​​the upper cavity, respectively.

[0008] A first heating device is used to heat a first region surrounding the central area of ​​the lower cavity;

[0009] A second heating device is used to heat a second region surrounding the first region;

[0010] The rotatable chuck is provided with a first processing liquid pipe and a second processing liquid pipe, which respectively pass through the rotatable chuck and are used to supply the first processing liquid and the second processing liquid to the central area of ​​the lower cavity.

[0011] Furthermore, the rotatable chuck is also provided with a first temperature regulating gas channel, which penetrates the rotatable chuck and is used to supply regulating gas to the central area of ​​the lower cavity for adjusting the temperature of the lower surface of the wafer.

[0012] Preferably, a first heater is provided at the inlet of the first temperature-regulating air duct;

[0013] The first heating device includes: a second temperature-regulating air passage penetrating the rotatable chuck; and a second heater disposed at the inlet of the second temperature-regulating air passage; and the rotatable chuck is provided with an intermittent first annular groove at the bottom of the inner cavity and communicating with the second temperature-regulating air passage, the first region being located inside the first annular groove;

[0014] The second heating device includes: a third temperature-regulating air passage penetrating the rotatable chuck; and a third heater disposed at the inlet of the third temperature-regulating air passage; and the rotatable chuck is provided with a discontinuous second annular groove at the bottom of the inner cavity and communicating with the third temperature-regulating air passage, the first annular groove being located within the second annular groove, and the second region being located between the first annular groove and the second annular groove.

[0015] Preferably, the wafer wet processing equipment further includes a fan filter disposed above the rotatable chuck, the fan filter being used to provide a dry, clean gas environment to the wafer wet processing equipment.

[0016] Preferably, the surface tension reducing fluid nozzle is also used to supply dry gas to the central area of ​​the upper cavity.

[0017] Preferably, the rotatable chuck is provided with a first processing liquid pipe outlet, a second processing liquid pipe outlet, and a first temperature regulating gas outlet at the bottom of the inner cavity, and the distance between any two of the first processing liquid pipe outlet, the second processing liquid pipe outlet, and the first temperature regulating gas outlet is in the range of 1 to 3 mm.

[0018] Preferably, the first heating device includes a first heat contact plate disposed within the rotatable chuck, and the second heating device includes a second heat contact plate disposed within the rotatable chuck, the second heat contact plate surrounding the first heat contact plate.

[0019] Preferably, the upper surfaces of the first thermal contact plate and the second thermal contact plate are provided with a plurality of thermally conductive protrusions.

[0020] Preferably, the distance between the plurality of thermally conductive bumps and the lower surface of the wafer is greater than 0.1 mm.

[0021] Another embodiment of the present invention provides a wafer wet processing method, comprising:

[0022] The wafer is placed in the inner cavity of the rotatable chuck of the wafer wet processing equipment. The inner cavity is divided into an upper cavity and a lower cavity according to the placement position of the wafer, and the rotatable chuck is rotated.

[0023] The first treatment fluid is supplied to the upper cavity and the lower cavity respectively until the upper cavity and the lower cavity are filled;

[0024] The second treatment fluid is supplied to the upper cavity and the lower cavity respectively until the upper cavity and the lower cavity are filled;

[0025] The second treatment liquid continues to be supplied to the upper cavity, while room temperature adjusting gas is supplied to the lower cavity.

[0026] Surface tension reducing fluid is supplied to the upper cavity until it covers the upper surface of the wafer, while the lower surface of the wafer is kept dry.

[0027] When the surface tension reducing fluid covers the upper surface of the wafer, the lower surface of the wafer is heated in a first zone to achieve thermal equilibrium in the central area of ​​the upper and lower surfaces of the wafer.

[0028] When the surface tension reducing liquid begins to evaporate, dry gas at room temperature is supplied to the upper cavity so that the surface tension reducing liquid dissipates from the center of the upper cavity to the periphery.

[0029] When the surface tension reducing liquid dissipates to the periphery and into the middle region of the upper cavity, the lower surface of the wafer is subjected to a second zone heating, which is used to achieve thermal equilibrium between the middle region of the upper and lower surfaces of the wafer.

[0030] When the surface tension reducing liquid dissipates to the peripheral area of ​​the upper cavity, the lower surface of the wafer is heated in a third zone to achieve thermal equilibrium between the peripheral areas of the upper and lower surfaces of the wafer.

[0031] After the surface tension reducing liquid has completely evaporated, room temperature adjusting gas is supplied to the lower cavity to cool the wafer.

[0032] Preferably, the first zone heating includes: supplying heating adjustment gas to the central zone of the lower cavity; or heating the central zone of the lower cavity through a first thermal contact plate.

[0033] Preferably, the second zone heating includes: supplying heating adjustment gas to the middle zone of the lower cavity; or heating the middle zone of the lower cavity through a first thermal contact plate.

[0034] Preferably, the third zone heating includes: supplying heating adjustment gas to the peripheral area of ​​the lower cavity; or heating the peripheral area of ​​the lower cavity through a second heat contact plate.

[0035] Preferably, the first treatment solution is an acidic or alkaline solution, the second treatment solution is an aqueous solution of carbon dioxide, and the surface tension reducing solution is an isopropanol solution.

[0036] Preferably, the purity of isopropanol in the isopropanol solution is greater than or equal to 99.99%.

[0037] Preferably, both the drying gas and the adjusting gas are nitrogen, the purity of the nitrogen is greater than or equal to 99.9%, and the flow rate of the nitrogen is in the range of 30 to 150 liters per minute.

[0038] Preferably, the temperature of the first treatment liquid and the second treatment liquid is room temperature, and the temperature range of the surface tension reducing liquid is 50 to 70°.

[0039] Preferably, the temperature of the heated adjusting gas is greater than or equal to the temperature of the surface tension reducing liquid; or the temperature of the first thermal contact plate is greater than or equal to the temperature of the surface tension reducing liquid.

[0040] Preferably, the temperature of the heated adjusting gas is greater than or equal to the temperature of the surface tension reducing liquid; or the temperature of the second thermal contact plate is greater than or equal to the temperature of the surface tension reducing liquid.

[0041] Preferably, the temperature range of the heating conditioning gas is 50 to 120°; or the temperature range of the first heat contact plate is 50 to 140°.

[0042] Preferably, the temperature range of the heated conditioning gas is 50 to 120°C; or the temperature range of the second heat contact plate is 50 to 140°C.

[0043] Preferably, when the lower surface of the wafer is heated in a first zone, a second zone, or a third zone, the temperature of the wafer surface is greater than or equal to the temperature of the surface tension reducing liquid.

[0044] Through the above technical solutions, the wafer wet processing equipment and method provided by the embodiments of the present invention heat the lower surface of the wafer during the evaporation of the surface tension reducing liquid, and keep the wafer surface at a high temperature until the surface tension reducing liquid is completely evaporated, so that the impurity gas in the equipment will not be adsorbed due to the high temperature of the wafer surface, thereby avoiding condensation defects. Attached Figure Description

[0045] Figure 1 This is a perspective view of a wafer wet processing apparatus according to an embodiment of the present invention;

[0046] Figure 2 This is a cross-sectional view of a wafer wet processing apparatus according to an embodiment of the present invention;

[0047] Figure 3 This is a top view of a wafer wet processing apparatus according to an embodiment of the present invention;

[0048] Figure 4 This is a cross-sectional view of a wafer wet processing apparatus according to another embodiment of the present invention;

[0049] Figure 5 This is a top view of a wafer wet processing apparatus according to another embodiment of the present invention;

[0050] Figure 6 This is a partially enlarged top view of a wafer wet processing apparatus according to another embodiment of the present invention;

[0051] Figures 7A to 7I These are cross-sectional views of the equipment corresponding to each step of the wafer wet processing method according to an embodiment of the present invention; and

[0052] Figures 8A to 8I This is a cross-sectional view of the equipment corresponding to each step of the wafer wet processing method according to another embodiment of the present invention.

[0053] Explanation of reference numerals in the attached figures

[0054] 1 Rotatable chuck 2 Inner cavity

[0055] 3 Upper cavity 4 Lower cavity

[0056] 5 First treatment fluid nozzle 6 Second treatment fluid nozzle

[0057] 7. Surface tension reducing fluid nozzle; 8. Fan filter

[0058] 9 Wafer 10 First Processing Fluid Pipeline

[0059] 11 Second processing fluid pipeline; 12 First temperature regulating gas duct

[0060] 13 First heater 14 Second temperature regulating gas duct

[0061] 15 Second heater 16 Third temperature regulating gas duct

[0062] 17 Third heater 18 First heat contact plate

[0063] 19 Second heat contact plate 20 Thermally conductive protrusion

[0064] 21 First treatment solution 22 Second treatment solution

[0065] 23 Surface tension reducing fluid 100 First treatment fluid pipeline outlet

[0066] 110 Second processing liquid pipeline outlet; 120 First temperature regulating gas pipeline outlet.

[0067] 140 First annular groove 160 Second annular groove Detailed Implementation

[0068] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0069] Figure 1 A perspective view of a wafer wet processing apparatus according to one embodiment of the present invention is shown. Figure 1 As shown, one embodiment of the present invention provides a wafer wet processing apparatus, which may include:

[0070] A rotatable chuck 1 has an inner cavity 2 for placing a wafer 9;

[0071] The first treatment fluid nozzle 5, the second treatment fluid nozzle 6, and the surface tension reducing fluid nozzle 7 are respectively disposed above the rotatable chuck 1, and are used to supply the first treatment fluid 21, the second treatment fluid 22, and the surface tension reducing fluid 23 to the center of the inner cavity 2, respectively.

[0072] like Figure 1 As shown, the first processing liquid nozzle 5, the second processing liquid nozzle 6, and the surface tension reducing liquid nozzle 7 can all be connected to a rotatable bracket. When any one of the first processing liquid nozzle 5, the second processing liquid nozzle 6, or the surface tension reducing liquid nozzle 7 is needed, the corresponding bracket can be rotated to align it towards the center of the inner cavity 2 and supply the corresponding processing solution. The surface tension reducing liquid nozzle 7 of this wafer wet processing equipment can also be used to supply drying gas to the central area of ​​the inner cavity 2.

[0073] In one embodiment of the present invention, the wafer wet processing equipment may further include a fan filter 8 disposed above the rotatable chuck 1. The fan filter 8 is used to provide a dry and pure gas environment to the wafer wet processing equipment, avoiding the wet processing of the wafer 9 in a humid and mixed gas environment, and providing necessary gas protection for the wet processing of the wafer 9.

[0074] Figure 2 A cross-sectional view of a wafer wet processing apparatus according to an embodiment of the present invention is shown. Figure 2 As shown, after the wafer 9 is placed into the rotatable chuck 1, the inner cavity 2 is divided into an upper cavity 3 and a lower cavity 4 according to the placement position of the wafer 9. The first processing liquid nozzle 5, the second processing liquid nozzle 6, and the surface tension reducing liquid nozzle 7 supply the first processing liquid 21, the second processing liquid 22, and the surface tension reducing liquid 23 to the central area of ​​the upper cavity 3, respectively. The surface tension reducing liquid nozzle 7 can also be used to supply drying gas to the central area of ​​the upper cavity 3.

[0075] like Figure 2 As shown, the wafer wet processing equipment may further include:

[0076] The first processing fluid pipe 10 and the second processing fluid pipe 11 respectively pass through the rotatable chuck 1 and are used to supply the first processing fluid 21 and the second processing fluid 22 to the central area of ​​the downward cavity 4.

[0077] The first temperature regulating gas channel 12 passes through the rotatable chuck 1 and is used to supply regulating gas for adjusting the temperature of the lower surface of the wafer 9 to the central area of ​​the lower cavity 4.

[0078] The wafer wet processing equipment provided in the embodiments of the present invention may further include:

[0079] The first heating device is used to heat a first region surrounding the central area of ​​the lower cavity 4;

[0080] The second heating device is used to heat the second region surrounding the first region.

[0081] The first heating device and the second heating device can be used to heat the lower cavity 4, thereby increasing the temperature of the lower surface of the wafer 9 through heat conduction, and further increasing the temperature of the upper surface of the wafer 9 to improve the condensation defects that occur when the surface tension reducing liquid 23 in the upper cavity 3 evaporates.

[0082] In one embodiment of the present invention, the wafer wet processing apparatus can heat the lower cavity 4 by means of a heater. Specifically, as shown... Figure 2As shown, a first heater 13 may be provided at the inlet of the first temperature regulating air passage 12; the first heating device may include a second temperature regulating air passage 14 passing through the rotatable chuck 1 and a second heater 15 provided at the inlet of the second temperature regulating air passage 14; the second heating device may include a third temperature regulating air passage 16 passing through the rotatable chuck 1 and a third heater 17 provided at the inlet of the third temperature regulating air passage 16.

[0083] In an embodiment of the present invention, the first heater 13, the second heater 15, and the third heater 17 may be resistance heaters.

[0084] In this embodiment, the first temperature regulating gas channel 12, the second temperature regulating gas channel 14, and the third temperature regulating gas channel 16 are respectively used to supply adjusting gas for adjusting the temperature of the lower surface of the wafer 9 to the central area, the middle area, and the peripheral area of ​​the lower cavity 4. The first heater 13, the second heater 15, and the third heater 17 are respectively used to heat the adjusting gas in the first temperature regulating gas channel 12, the second temperature regulating gas channel 14, and the third temperature regulating gas channel 16, so that the adjusting gas changes from room temperature to high temperature. After the high temperature adjusting gas is introduced into the lower cavity 4, the temperature of the lower surface of the wafer 9 is increased by heat conduction, thereby increasing the temperature of the upper surface of the wafer 9 to improve the condensation defects that occur when the surface tension reducing liquid 23 in the upper cavity 3 evaporates.

[0085] Figure 3 A top view of a wafer wet processing apparatus according to one embodiment of the present invention is shown. Figure 3 As shown, the rotatable chuck 1 has a first processing liquid outlet 100, a second processing liquid outlet 110, and a first temperature-regulating gas outlet 120 at the bottom of the inner cavity 2. All three outlets are circular. The rotatable chuck 1 also has an intermittent first annular groove 140 at the bottom of the inner cavity 2, which communicates with the second temperature-regulating gas channel 14. The first region is located inside the first annular groove 140, specifically between the first annular groove 140 and the opening of the first temperature-regulating gas channel 12 at the bottom of the inner cavity 2. The rotatable chuck 1 is also provided with a second annular groove 160 at the bottom of the inner cavity 2, which is intermittent and communicates with the third temperature regulating air passage 16. The first annular groove 140 is located inside the second annular groove 160 and between the outlet 120 of the first temperature regulating air passage. The second region is located between the first annular groove 140 and the second annular groove 160.

[0086] The spacing between any two of the first treatment fluid pipeline outlet 100, the second treatment fluid pipeline outlet 110, and the first temperature-regulating gas outlet 120 can be selected within a wide range, preferably, the spacing is between 1 and 3 millimeters.

[0087] Figure 4 A cross-sectional view of a wafer wet processing apparatus according to another embodiment of the present invention is shown. Figure 5 A top view of a wafer wet processing apparatus according to another embodiment of the present invention is shown. In another embodiment of the present invention, the wafer wet processing apparatus can heat the lower cavity 4 by providing a thermal contact plate within a rotatable chuck 1. Specifically, as Figure 4 and Figure 5 As shown, the first heating device may include a first heat contact plate 18 disposed in the rotatable chuck 1, and the second heating device may include a second heat contact plate 19 disposed in the rotatable chuck 1, the second heat contact plate 19 surrounding the outer periphery of the first heat contact plate 18.

[0088] In an embodiment of the present invention, the first thermal contact plate 18 and the second thermal contact plate 19 can be resistive thermal contact plates.

[0089] In this embodiment, the first temperature regulating gas channel 12 is used to supply the central area of ​​the lower cavity 4 with regulating gas for adjusting the temperature of the lower surface of the wafer 9, and the first thermal contact plate 18 and the second thermal contact plate 19 are used to heat the lower surface of the wafer 9 to increase the temperature of the lower surface of the wafer 9, thereby improving the condensation defects that occur when the surface tension reducing liquid 23 evaporates.

[0090] Figure 6 A partially enlarged top view of a wafer wet processing apparatus according to another embodiment of the present invention is shown. Figure 4 and Figure 6 As shown, the upper surfaces of the first thermal contact pad 18 and the second thermal contact pad 19 are provided with a plurality of thermally conductive protrusions 20. The function of the plurality of thermally conductive protrusions 20 is to improve the thermal conductivity between the first thermal contact pad 18, the second thermal contact pad 19 and the lower cavity 4, thereby effectively and stably increasing the temperature of the lower surface of the wafer 9.

[0091] The spacing between the multiple thermally conductive bumps 20 and the lower surface of the wafer 9 can be selected within a wide range. Preferably, in order not to cause excessive obstruction to the flow of the processing liquid in the lower cavity 4 and to avoid water stains, the spacing between the multiple thermally conductive bumps 20 and the lower surface of the wafer 9 can be greater than 0.1 mm.

[0092] In the wafer wet processing, to prevent structural collapse on the wafer 9 surface caused by capillary forces generated during the evaporation of the processing solution, a surface tension reducing fluid 23 is typically introduced to reduce these capillary forces, thereby improving the structural collapse problem on the wafer 9 surface. However, during the evaporation of the surface tension reducing fluid 23, the latent heat of phase transition of the fluid causes a drop in the temperature of the wafer 9 surface. Gas impurities in the wafer wet processing equipment may condense and adsorb onto the wafer 9 surface, forming condensation defects. The wafer wet processing equipment provided by the embodiments of the present invention can heat the lower surface of the wafer 9 during the evaporation of the surface tension reducing fluid 23 to increase the temperature of the lower surface of the wafer 9, thereby increasing the temperature of the upper surface of the wafer 9 and improving the condensation defects that occur during the evaporation of the surface tension reducing fluid 23 in the upper cavity 3.

[0093] Another aspect of the present invention provides a wafer wet processing method, which can perform wet processing on wafer 9 using the above-mentioned wafer wet processing equipment, and can avoid the above-mentioned condensation defects during the wet processing of wafer 9.

[0094] Figures 7A to 7I A cross-sectional view of a wafer wet processing apparatus corresponding to each step of a wafer wet processing method according to an embodiment of the present invention is shown. The wafer wet processing method of this embodiment includes:

[0095] like Figure 2 As shown, the wafer 9 is placed in the inner cavity 2 of the rotatable chuck 1 of the wafer wet processing equipment. The inner cavity 2 is divided into an upper cavity 3 and a lower cavity 4 according to the placement position of the wafer 9, and the rotatable chuck 1 is rotated.

[0096] like Figure 7A As shown, the first treatment liquid 21 is supplied from the first treatment liquid nozzle 5 and the first treatment liquid pipe 10 to the upper cavity 3 and the lower cavity 4 respectively until the upper cavity 3 and the lower cavity 4 are filled.

[0097] like Figure 7B As shown, the second processing liquid 22 is supplied from the second processing liquid nozzle 6 and the second processing liquid pipe 11 to the upper cavity 3 and the lower cavity 4 until the upper cavity 3 and the lower cavity 4 are filled.

[0098] like Figure 7C As shown, the second processing liquid 22 continues to be supplied to the upper cavity 3, while room temperature adjusting gas is supplied to the lower cavity 4 from the first temperature regulating gas channel 12.

[0099] like Figure 7D As shown, surface tension reducing fluid 23 is supplied from the surface tension reducing fluid nozzle 7 to the upper cavity 3 until it covers the upper surface of the wafer 9, while keeping the lower surface of the wafer 9 dry.

[0100] like Figure 7E As shown, the first heater 13 is turned on to heat the regulating gas in the first temperature regulating gas channel 12 to achieve thermal equilibrium in the central area of ​​the upper and lower surfaces of the wafer 9.

[0101] like Figure 7F As shown, when the surface tension reducing liquid 23 begins to evaporate, dry gas at room temperature is supplied from the surface tension reducing liquid nozzle 7 to the upper cavity 3 so that the surface tension reducing liquid 23 dissipates from the center of the upper cavity 3 to the periphery.

[0102] like Figure 7G As shown, when the surface tension reducing liquid 23 dissipates to the middle area of ​​the inner cavity 2 (i.e. the edge of the first area), the adjusting gas is supplied to the lower cavity 4 from the second temperature regulating gas channel 14, and the second heater 15 is turned on to heat the adjusting gas in the second temperature regulating gas channel 14 to achieve thermal equilibrium in the middle area of ​​the upper and lower surfaces of the wafer 9.

[0103] like Figure 7H As shown, when the surface tension reducing liquid 23 dissipates to the periphery of the inner cavity 2 (i.e. the edge of the second region), the adjusting gas is supplied to the lower cavity 4 from the third temperature regulating gas channel 16, and the third heater 17 is turned on to heat the adjusting gas in the third temperature regulating gas channel 16 to achieve thermal equilibrium of the periphery of the upper and lower surfaces of the wafer 9.

[0104] like Figure 7I As shown, when the surface tension reducing liquid 23 has completely evaporated, the first heater 13, the second heater 15 and the third heater 17 are turned off, and room temperature regulating gas is supplied to the lower cavity 4 from the first temperature regulating gas channel 12, the second temperature regulating gas channel 14 and the third temperature regulating gas channel 16 to cool the wafer 9.

[0105] Figures 8A to 8I A cross-sectional view of a wafer wet processing apparatus corresponding to each step of a wafer wet processing method according to another embodiment of the present invention is shown. The wafer wet processing method of this embodiment includes:

[0106] like Figure 2 As shown, the wafer 9 is placed in the inner cavity 2 of the rotatable chuck 1 of the wafer wet processing equipment. The inner cavity 2 is divided into an upper cavity 3 and a lower cavity 4 according to the placement position of the wafer 9, and the rotatable chuck 1 is rotated.

[0107] like Figure 8A As shown, the first treatment liquid 21 is supplied from the first treatment liquid nozzle 5 and the first treatment liquid pipe 10 to the upper cavity 3 and the lower cavity 4 respectively until the upper cavity 3 and the lower cavity 4 are filled.

[0108] like Figure 8BAs shown, the second processing liquid 22 is supplied from the second processing liquid nozzle 6 and the second processing liquid pipe 11 to the upper cavity 3 and the lower cavity 4 until the upper cavity 3 and the lower cavity 4 are filled.

[0109] like Figure 8C As shown, the second processing liquid 22 continues to be supplied to the upper cavity 3, while room temperature adjusting gas is supplied to the lower cavity 4 from the first temperature regulating gas channel 12.

[0110] like Figure 8D As shown, surface tension reducing fluid 23 is supplied from the surface tension reducing fluid nozzle 7 to the upper cavity 3 until the upper cavity 3 is filled;

[0111] like Figure 8E As shown, the first thermal contact plate 18 is opened to heat the central and intermediate areas of the bottom of the lower cavity 4 to achieve thermal equilibrium in the central and intermediate areas of the upper and lower surfaces of the wafer 9, while room temperature regulating gas is no longer supplied to the lower cavity 4.

[0112] like Figure 8F As shown, when the surface tension reducing liquid 23 begins to evaporate, dry gas at room temperature is supplied from the surface tension reducing liquid nozzle 7 to the upper cavity 3 so that the surface tension reducing liquid 23 dissipates from the center of the upper cavity 3 to the periphery.

[0113] like Figure 8G and 8H As shown, when the surface tension reducing liquid 23 dissipates to the middle area of ​​the inner cavity 2 (i.e. the edge of the first thermal contact plate 18), the second thermal contact plate 19 is opened to heat the adjusting gas in the lower cavity 4 to achieve thermal equilibrium between the peripheral areas of the upper and lower surfaces of the wafer 9, until the surface tension reducing liquid 23 is completely evaporated.

[0114] like Figure 8I As shown, when the surface tension reducing liquid 23 has completely evaporated, the first thermal contact plate 18 and the second thermal contact plate 19 are closed, and room temperature adjusting gas is supplied to the lower cavity 4 from the first temperature regulating gas channel 12 to cool the wafer 9.

[0115] In embodiments of the present invention, the first treatment liquid 21 can be an acidic solution or an alkaline solution, the second treatment liquid 22 can be an aqueous solution of carbon dioxide, and the surface tension reducing liquid 23 can be an isopropanol solution.

[0116] The weight percentage of isopropanol in the isopropanol solution is greater than or equal to 99.99%.

[0117] The temperature of the first treatment liquid 21 and the second treatment liquid 22 is room temperature, and the temperature range of the surface tension reducing liquid 23 is 50 to 70°.

[0118] In embodiments of the present invention, both the drying gas and the conditioning gas can be nitrogen, with a nitrogen purity greater than or equal to 99.9%, and a nitrogen gas flow rate ranging from 30 to 150 liters per minute. Specifically, to ensure more uniform temperature distribution in the central, intermediate, and peripheral regions of wafer 9, the gas flow rate in the second temperature-regulating gas channel 14 can be slightly less than that in the first temperature-regulating gas channel 12; the gas flow rate in the third temperature-regulating gas channel 16 can also be slightly less than that in the second temperature-regulating gas channel 14. Preferably, the nitrogen flow rate in the first temperature-regulating gas channel 12 ranges from 30 to 150 liters per minute, the nitrogen flow rate in the second temperature-regulating gas channel 14 is 20 to 100 liters per minute, and the nitrogen flow rate in the third temperature-regulating gas channel 16 is 10 to 100 liters per minute.

[0119] The temperature of the heated adjusting gas can be greater than or equal to the temperature of the surface tension reducing fluid 23, preferably, the temperature range of the heated adjusting gas is 50 to 120°C. The temperature of the first heat contact plate 18 can be greater than or equal to the temperature of the surface tension reducing fluid 23, preferably, the temperature range of the first heat contact plate 18 is 50 to 140°C; the temperature of the second heat contact plate 19 can be greater than or equal to the temperature of the surface tension reducing fluid 23, preferably, the temperature range of the second heat contact plate 19 is 50 to 140°C.

[0120] In an embodiment of the present invention, during the evaporation of the surface tension reducing liquid 23, the temperature of the surface of wafer 9 (more specifically, the upper surface) can be greater than or equal to the temperature of the surface tension reducing liquid 23. By setting such a temperature gradient, during the wet processing of wafer 9, the high-temperature adjusting gas or hot contact plate in the lower cavity 4 of the wafer wet processing equipment can continuously, effectively, and stably increase the temperature of the surface of wafer 9 (including the upper and lower surfaces) through heat conduction or radiation, thereby better suppressing the condensation and adsorption of gaseous impurities in the wafer wet processing equipment, and further overcoming condensation defects during the wet processing of wafer 9.

[0121] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various specific technical features in any suitable manner. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately. However, these simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A wafer wet processing method, characterized in that, include: The wafer is placed in the inner cavity of the rotatable chuck of the wafer wet processing equipment. The inner cavity is divided into an upper cavity and a lower cavity according to the placement position of the wafer, and the rotatable chuck is rotated. The first treatment fluid is supplied to the upper cavity and the lower cavity respectively until the upper cavity and the lower cavity are filled; The second treatment fluid is supplied to the upper cavity and the lower cavity respectively until the upper cavity and the lower cavity are filled; The second treatment liquid continues to be supplied to the upper cavity, while room temperature adjusting gas is supplied to the lower cavity. Surface tension reducing fluid is supplied to the upper cavity until it covers the upper surface of the wafer, while the lower surface of the wafer is kept dry. When the surface tension reducing fluid covers the upper surface of the wafer, the lower surface of the wafer is heated in a first zone to achieve thermal equilibrium in the central area of ​​the upper and lower surfaces of the wafer. When the surface tension reducing liquid begins to evaporate, dry gas at room temperature is supplied to the upper cavity so that the surface tension reducing liquid dissipates from the center of the upper cavity to the periphery. When the surface tension reducing liquid dissipates to the periphery and into the middle region of the upper cavity, the lower surface of the wafer is subjected to a second zone heating, which is used to achieve thermal equilibrium between the middle region of the upper and lower surfaces of the wafer. When the surface tension reducing liquid dissipates to the peripheral area of ​​the upper cavity, the lower surface of the wafer is heated in a third zone to achieve thermal equilibrium between the peripheral areas of the upper and lower surfaces of the wafer. After the surface tension reducing liquid has completely evaporated, room temperature adjusting gas is supplied to the lower cavity to cool the wafer.

2. The method according to claim 1, characterized in that, The first zone heating includes: Heated regulating gas is supplied to the central region of the lower cavity; or The central area of ​​the lower cavity is heated by the first thermal contact plate.

3. The method according to claim 1, characterized in that, The second zone heating includes: Heated regulating gas is supplied to the middle region of the lower cavity; or The middle area of ​​the lower cavity is heated by the first thermal contact plate.

4. The method according to claim 1, characterized in that, The heating of the third zone includes: Heated regulating gas is supplied to the peripheral area of ​​the lower cavity; or The peripheral area of ​​the lower cavity is heated by the second heat contact plate.

5. The method according to claim 1, characterized in that, The first treatment solution is an acidic or alkaline solution, the second treatment solution is an aqueous solution of carbon dioxide, and the surface tension reducing solution is an isopropanol solution.

6. The method according to claim 5, characterized in that, The isopropanol solution contains an isopropanol weight percentage greater than or equal to 99.99%.

7. The method according to claim 5, characterized in that, Both the drying gas and the adjusting gas are nitrogen, the purity of the nitrogen is greater than or equal to 99.9%, and the flow rate of the nitrogen is in the range of 30 to 150 liters per minute.

8. The method according to claim 1, characterized in that, The temperature of the first and second treatment solutions is room temperature, and the temperature range of the surface tension reducing solution is 50 to 70°C.

9. The method according to claim 2 or 3, characterized in that, The temperature of the heated adjusting gas is greater than or equal to the temperature of the surface tension reducing liquid; or The temperature of the first thermal contact plate is greater than or equal to the temperature of the surface tension reducing fluid.

10. The method according to claim 4, characterized in that, The temperature of the heated adjusting gas is greater than or equal to the temperature of the surface tension reducing liquid; or The temperature of the second thermal contact plate is greater than or equal to the temperature of the surface tension reducing fluid.

11. The method according to claim 9, characterized in that, The temperature range of the heated conditioning gas is 50 to 120°C; or The temperature range of the first thermal contact plate is 50 to 140°C.

12. The method according to claim 10, characterized in that, The temperature range of the heated conditioning gas is 50 to 120°C; or The temperature range of the second heat contact plate is 50 to 140°C.

13. The method according to claim 1, characterized in that, When the lower surface of the wafer is heated in a first zone, a second zone, or a third zone, the temperature of the wafer surface is greater than or equal to the temperature of the surface tension reducing liquid.

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