CN106971958A - Single wafer wet processing apparatus - Google Patents

Abstract

The invention provides a single wafer wet processing device for preventing the bottom surface of the edge of a wafer from being corroded by chemical liquid or corrosive gas. The back rinse seat includes an annular flat surface having a predetermined spacing from a bottom surface of the wafer. The annular gas nozzle is arranged on the annular plane of the back washing seat, has a preset distance with the edge of the wafer, and has a preset included angle with the annular plane in the gas spraying direction so as to form a gas wall between the annular plane and the bottom surface of the wafer. The preset distance is between 2mm and 5mm, the preset distance is between 10mm and 15mm, and the preset included angle is between 30 degrees and 45 degrees, so that the optimal wafer bottom surface protection effect can be obtained.

Description

Single Wafer Wet Processor

【Technical field】

The invention relates to a wafer processing device, in particular to a single wafer wet processing device suitable for preventing corrosion of the bottom surface of the wafer edge.

【Background technique】

Typically microelectronic components are fabricated on the front or device side of a semiconductor wafer. In the process of semiconductor wafers, it is necessary to perform multiple process steps on the front side of the semiconductor wafers, such as spraying treatment liquids (such as chemicals or deionized water, etc.) on the surface of the wafers to etch and clean the wafers Isohumid treatment procedure. Please refer to FIG. 1 . FIG. 1 is a schematic cross-sectional view of a conventional spin etching cleaning machine. The existing rotary etching cleaning machine 10 includes an etching chamber 12, and a stage 14 is provided in the etching chamber 12 to carry and fix a wafer W. The rotating shaft 16 below the stage 14 can be adjusted according to various process parameters. Set the requirement, perform high and low speed rotation, and then drive the wafer W to rotate, and the etching liquid 19 flows down from the liquid supply unit 18 above the wafer W to etch the front side of the wafer W.

When the above-mentioned etching is performed again, if the process parameters of the wafer W are low, the chemical liquid film or corrosive gas on the front of the wafer W may flow from the edge of the wafer W to the wafer due to the decrease in the centrifugal force of the rotation. Corrosion occurs on the bottom surface of the wafer W and the carrier 14 , and corrosion pollutants, such as metal particles, residues or films, etc., are formed on the bottom surface of the wafer W. If the above substances are not removed, they will damage or contaminate the components on the front side of the wafer. For example, some metal materials used in the process, such as copper, may be stained back from the bottom of the wafer to the front of the wafer, which will cause defects in microelectronic components and reduce manufacturing yield. Therefore, when performing the above-mentioned wet process, protection measures for the bottom surface of the wafer W are crucial considerations in equipment design.

【Content of invention】

In view of this, in order to prevent the bottom surface of the wafer edge from corroding, the object of the present invention is to provide a single wafer wet processing device, which generates a gas wall on the bottom surface of the wafer edge through the annular gas nozzle to isolate the etching solution or corrode Corrosion of the bottom surface of the wafer by the inert gas overcomes the problem of contamination on the back of the wafer in the prior art.

To achieve the above purpose, the present invention provides a single wafer wet processing device for preventing corrosion of the bottom surface of the wafer edge, which includes a rotary chuck, a back cleaning seat and an annular gas nozzle. The spin chuck is used to hold and rotate a wafer. The back wash seat is arranged around the rotary chuck, and includes an annular plane, the annular plane has a predetermined distance from the bottom surface of the wafer, and the back wash seat is in a right-angle structure at the outer periphery of the annular plane. The annular gas nozzle is set on the annular plane of the back wash seat, and is at a predetermined distance from the edge of the wafer, and the direction of the ejected gas forms a predetermined angle with the annular plane, so as to An air wall is formed between the annular plane and the bottom surface of the wafer. The predetermined distance is between 2 mm and 5 mm, the predetermined distance is between 10 mm and 15 mm, and the predetermined included angle is between 30 degrees and 45 degrees.

In a preferred embodiment, the outer periphery of the annular plane is approximately equal to the edge of the wafer, and the right-angle structure is approximately flush with the edge of the wafer.

In a preferred embodiment, the predetermined distance is 3mm.

In a preferred embodiment, the predetermined distance is 13mm.

In a preferred embodiment, the predetermined included angle is 40 degrees.

In a preferred embodiment, the annular gas nozzle is an annular oblique slot structure on the back washing seat.

In a preferred embodiment, the annular gas nozzle is used to spray nitrogen, and the flow rate of nitrogen spray is between 100 LPM (liter per minute) and 150 LPM. Preferably, the flow rate of nitrogen injection is 120 LPM.

In a preferred embodiment, the single wafer wet processing device further includes an inner annular gas nozzle, which is set on the annular plane of the back wash seat and is concentric with the annular gas nozzle for An air wall is formed between the annular plane and the bottom surface of the wafer.

In a preferred embodiment, the single-wafer wet processing device further includes a pure water nozzle, and the pure water nozzle is set on the annular plane of the back wash seat, and is used to spray all the water on the edge of the wafer. Rinse the underside.

Compared with the prior art, the single wafer wet processing device of the present invention sets the predetermined distance between 2mm and 5mm, the predetermined distance between 10mm and 15mm, and the predetermined included angle between 30° and 45° The degree can be optimized to block the etching solution or corrosive gas that wants to flow to the bottom surface of the wafer, so as to obtain an excellent protection effect. In addition, preferably, setting the predetermined distance to 3 mm, the predetermined distance to 13 mm, the predetermined included angle to 40 degrees, and the flow rate of nitrogen gas to 120 LPM can obtain the best protection effect on the bottom surface of the wafer.

In order to make the above and other purposes, features, and advantages of the present invention more obvious and understandable, the detailed description is as follows in conjunction with the accompanying drawings:

【Description of drawings】

Fig. 1 is the schematic sectional view of existing rotary etching cleaning machine platform;

2 is a schematic top view of a single wafer wet processing device according to a first preferred embodiment of the present invention;

Fig. 3 is a schematic sectional view of Fig. 2 along the line A-A';

FIG. 4 is a partial enlarged view of the backwash seat and the wafer in FIG. 3;

5 is a schematic top view of a single wafer wet processing device according to a second preferred embodiment of the present invention;

Fig. 6 is a schematic cross-sectional view of Fig. 5 along the line B-B'.

【detailed description】

Several preferred embodiments of the present invention are described in detail with the help of the accompanying drawings and the following descriptions. In different drawings, the same reference numerals represent the same or similar components.

Please refer to FIG. 2 and FIG. 3. FIG. 2 is a schematic top view of a single-wafer wet processing device according to a first preferred embodiment of the present invention, and FIG. 3 is a schematic cross-sectional view along line A-A' in FIG. 2 . As shown in the figure, the single wafer wet processing device 20 of the first preferred embodiment is used to prevent the bottom surface 34 of the wafer edge 32 from being corroded by the etching solution 19 or gas. For clarity, the wafer W is not shown in FIG. 2 . In detail, as shown in FIG. 3 , the single wafer wet processing device 20 of this embodiment includes a rotary chuck 22 , a backwash seat 24 , an annular gas nozzle 26 and a pure water spray head 28 . The above-mentioned components can be disposed in an etching chamber (not shown in the figure), and a liquid supply unit 18 is also provided on the rotary chuck 22 to provide fluids such as etching liquid 19 or cleaning liquid.

As shown in FIG. 3 , the spin chuck (Chuck) 22 is used to hold and rotate the wafer W. Preferably, the spin chuck 22 can generate a vacuum negative pressure to suction and fix the wafer W. In addition, the spin chuck 22 is connected to a rotating shaft 16 capable of rotating at high and low speeds for rotating the wafer W. As shown in FIG.

As shown in FIGS. 2 and 3 , the back wash seat 24 is arranged around the rotary chuck 22, and the back wash seat 24 includes an annular plane 242, and the annular plane 242 has the same shape as the bottom surface 34 of the wafer W. A predetermined distance P, that is, the annular plane 242 is slightly lower than the plane of the spin chuck 22 , so that the wafer W will not touch the annular plane 242 . The predetermined distance P is between 2mm and 5mm, which can obtain a preferable anti-erosion effect. In this embodiment, the predetermined distance P is 3mm. The back washing seat 24 has a right angle structure R at the outer peripheral edge 244 of the annular plane 242, that is to say, the back washing seat 24 of this embodiment will not have an arc or guide at the outer peripheral edge 244 of the annular plane 242. The structure of the corner is used to prevent the bottom surface 34 of the wafer W from being eroded by the turbulence of the air flow. It should be noted that the outer periphery 244 of the annular plane 242 is approximately equal to the wafer edge 32, and the right angle structure R is approximately aligned with the wafer edge 32, that is, the outer periphery 244 of the annular plane 242 is approximately equal to the wafer edge 32. The diameter of circle W defines the circle.

Please refer to FIG. 4 . FIG. 4 is a partially enlarged view of the backwash seat 24 and the wafer in FIG. 3 . The annular gas nozzle 26 is provided on the annular plane 242 of the backwash seat 24, and is at a predetermined distance D from the edge of the wafer 32, and the direction of the ejected gas (not shown) (that is, the opening tangent direction) and the annular plane 242 form a predetermined angle C, in order to form an air wall or air cushion between the annular plane 242 and the bottom surface 34 of the wafer W, so as to block the etching solution 19 Or gas attack on the bottom surface 34 of the wafer. Specifically, the annular gas nozzle 26 is an annular oblique slot structure 262 on the back washing seat 24 . Furthermore, the predetermined distance D is between 10 mm and 15 mm, which can obtain a preferred air wall or air cushion effect. In this embodiment, the predetermined distance D is 13 mm. In addition, the predetermined included angle C is between 30 degrees and 45 degrees, which can also obtain a preferred air wall or air cushion effect. In this embodiment, the predetermined included angle C is 40 degrees. It is worth mentioning that the annular gas nozzle 26 is used to spray nitrogen gas, and the flow rate of the nitrogen gas sprayed is between 100 LPM (liter per minute) and 150 LPM, so as to obtain a preferable effect of forming a gas wall. In this embodiment, the flow rate of nitrogen injection is 120 LPM.

Please refer to Fig. 2, in addition to using the above-mentioned annular gas nozzle 26 to block the etchant 19 or gas, the single wafer wet processing device 20 of the present embodiment further includes a pure water nozzle 28, and the pure water nozzle 28 is opened on the back wash. The annular plane 242 of the seat 24 is used to spray deionized water (DI water) to rinse the bottom surface 34 of the wafer edge 32 to further protect the bottom surface 34 .

Please refer to FIG. 5 and FIG. 6. FIG. 5 is a schematic top view of a single-wafer wet processing device according to a second preferred embodiment of the present invention, and FIG. 6 is a schematic cross-sectional view along line B-B' in FIG. 5 . The single wafer wet processing device 40 of this embodiment is used to prevent the bottom surface 34 of the wafer edge 32 from being corroded by the etching solution 19 or gas. The single wafer wet processing device 40 of this embodiment includes a rotary chuck 22 , a back wash seat 24 , an annular gas nozzle 26 , a pure water spray head 28 and an inner annular gas nozzle 27 . The above-mentioned components can be disposed in an etching chamber (not shown in the figure), and a liquid supply unit 18 is also provided on the rotary chuck 22 to provide fluids such as etching liquid 19 or cleaning liquid. Different from the above-mentioned first embodiment, the single wafer wet processing device 40 of this embodiment further includes an inner annular gas nozzle 27, and the inner annular gas nozzle 27 is provided on the annular plane 242 of the back wash seat 24, And it is concentric with the annular gas nozzle 26 to form a gas wall between the annular plane 242 and the bottom surface 34 of the wafer W to further strengthen the barrier of gas (such as acid gas).

Furthermore, through the inner annular gas nozzle 27 arranged on the inner ring of the annular gas nozzle 26, the single wafer wet processing device 40 of the second preferred embodiment can be used for large-sized wafers such as 12, 18 inches, etc., to obtain Excellent anti-erosion effect. In addition, the annular gas nozzle 26 and the inner annular gas nozzle 27 may be respectively connected to a first gas source 271 and a second gas source 272 . The first gas source 271 and the second gas source 272 can supply nitrogen to the annular gas nozzle 26 and the inner annular gas nozzle 27 at the same time, and the first gas source 271 and the second gas source 272 can also be controlled respectively without supplying nitrogen at the same time, or Only one of the annular gas nozzle 26 and the inner annular gas nozzle 27 is supplied.

In summary, the single wafer wet processing devices 20 and 40 of the present invention set the predetermined pitch P between 2mm and 5mm, the predetermined distance D between 10mm and 15mm, and the predetermined included angle C between 30° to 45° can optimally block the etchant 19 or gas that is intended to flow to the bottom surface 34 of the wafer W, thereby obtaining an excellent protection effect. In addition, preferably, setting the predetermined distance to 3 mm, the predetermined distance to 13 mm, the predetermined included angle to 40 degrees, and the flow rate of the nitrogen gas to 120 LPM can obtain the best protection effect on the bottom surface 34 .

Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Those skilled in the art to which the present invention belongs can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be defined by the appended claims.

Although the present invention has been disclosed above with preferred embodiments, the above preferred embodiments are not intended to limit the present invention. Those skilled in the art can make various modifications and modifications without departing from the spirit and scope of the present invention. , so the protection scope of the present invention shall be determined by the scope defined in the claims.

Claims (10)

1. A single wafer wet processing device, used to prevent the bottom surface corrosion of the wafer edge, is characterized in that, comprising: Rotary chuck for holding and rotating a wafer; The back wash seat is arranged around the rotary chuck, and includes an annular plane, the annular plane has a predetermined distance from the bottom surface of the wafer, and the back wash seat is a right-angle structure at the outer periphery of the annular plane; and The annular gas nozzle is set on the annular plane of the backwash seat, and is at a predetermined distance from the edge of the wafer, and the direction of the ejected gas forms a predetermined angle with the annular plane, for an air wall is formed between the annular plane and the bottom surface of the wafer; Wherein the predetermined distance is between 2 mm and 5 mm, the predetermined distance is between 10 mm and 15 mm, and the predetermined included angle is between 30 degrees and 45 degrees. 2 . The single wafer wet processing device according to claim 1 , wherein the outer periphery of the annular plane is approximately equal to the edge of the wafer, and the right-angle structure is approximately aligned with the edge of the wafer. 3 . 3 . The single wafer wet processing device according to claim 1 , wherein the predetermined distance is 3 mm. 4 . 4. The single wafer wet processing apparatus according to claim 1, wherein the predetermined distance is 13 mm. 5. The single wafer wet processing apparatus according to claim 1, wherein the predetermined included angle is 40 degrees. 6 . The single wafer wet processing device according to claim 1 , wherein the annular gas nozzle is an annular oblique slot structure on the back wash seat. 7 . 7 . The single wafer wet processing device according to claim 1 , wherein the annular gas nozzle is used to spray nitrogen gas, and the flow rate of nitrogen gas sprayed is between 100 LPM (liter per minute) and 150 LPM. 8 . 8 . The single wafer wet processing device according to claim 7 , wherein the flow rate of the nitrogen gas is 120 LPM. 9. The single wafer wet processing device according to claim 1, further comprising an inner annular gas nozzle, which is set on the annular plane of the back wash seat, and is in the same shape as the annular gas nozzle. concentric circles for forming an air wall between the annular plane and the bottom surface of the wafer. 10. The single wafer wet processing device according to claim 1, further comprising a pure water nozzle, the pure water nozzle is provided on the annular plane of the back cleaning seat, for The underside of the wafer edge is rinsed.