JP2007081432A - Method and device for manufacturing of semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a deterioration of a reaction uniformity to a chemical in a semiconductor substrate surface, which is caused by a temperature distribution of the treatment chemicals on the semiconductor substrate surface when the semiconductor substrate is processed with the hot chemicals. <P>SOLUTION: In the manufacturing method, a nozzle support arm 18 on which a plurality of chemical nozzles 4 which eject chemicals at the chemical processing temperature are mounted, corresponding to the plurality of different positions in the diametrical direction of the substrate 1, is arranged above the semiconductor substrate 1. The chemical is ejected from the plurality of chemical nozzles 4, while rotating the nozzle support arm 18 around an axis of rotation of the semiconductor substrate 1 for the reverse direction against the rotation direction of the semiconductor substrate 1. By rotating the surface of the semiconductor substrate 1, the high temperature chemical is supplied simultaneously on the plurality of different positions of the semiconductor substrate 1 in the diametrical direction. Thereby, the variation of the temperature of the chemical on the substrate surface is decreased, and the reaction uniformity of the chemical on the substrate surface can be enhanced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method and apparatus for manufacturing a semiconductor device, and relates to a wet processing apparatus generally used in a manufacturing process of a semiconductor device, in particular, a semiconductor substrate cleaning apparatus.

With the miniaturization and high integration of semiconductor devices, the miniaturization of element patterns is increasing. In addition, the diameter of semiconductor substrates is increasing. Therefore, the number of single-wafer processing apparatuses is increasing in semiconductor manufacturing apparatuses (see, for example, Patent Documents 1 and 2). In such a single wafer cleaning device, for example, the temperature of the processing semiconductor substrate and the processing chemical solution for processing the high temperature chemical solution, the processing atmosphere in order to finish wet etching / cleaning (contamination removal, particle removal) in a short time. Is required to be accurately controlled, and cleaning can be performed stably. In particular, temperature control is very sensitive to etching characteristics related to changes in etching rate, flatness after wafer processing, and the like, and important control is required.
Japanese Patent Laid-Open No. 5-121388 (FIG. 1) Japanese Patent Laid-Open No. 2002-231694 (FIG. 1)

  However, in the conventional cleaning method, when a semiconductor substrate is processed in a high temperature chemical solution in a sheet mode, even if the substrate is rotated at a high speed, the chemical temperature varies within the surface. In other words, the temperature distribution differs between the part where the chemical solution and the substrate first contact each other and the other part, and it is difficult to stably control the treatment temperature of the chemical solution described above. Met. In this way, the temperature distribution of the processing chemical solution occurs on the surface of the semiconductor substrate, and the uniformity of the reaction to the chemical solution within the substrate surface, such as the in-plane uniformity of etching, such as the etching rate to the substrate being different, is reduced. There was a problem of letting it go.

  An object of the present invention is to provide a semiconductor device manufacturing method and a manufacturing apparatus capable of eliminating a temperature difference of a processing chemical solution within a surface of a semiconductor substrate and improving a reaction uniformity within the substrate surface to perform high temperature chemical processing. is there.

  A method for manufacturing a semiconductor device according to claim 1 of the present invention is a method for manufacturing a semiconductor device in which a chemical solution is applied to the surface of the semiconductor substrate by supplying a chemical solution to the surface of the semiconductor substrate. A chemical solution having a higher predetermined processing temperature is simultaneously supplied to a plurality of positions on the surface of the semiconductor substrate which are different in the diameter direction of the semiconductor substrate.

  The semiconductor device manufacturing method according to claim 2 is the semiconductor device manufacturing method according to claim 1, wherein a plurality of chemical nozzles for discharging a chemical liquid at a processing temperature are at a plurality of positions different in a diameter direction of the semiconductor substrate. The nozzle support arm arranged corresponding to the above is disposed above the semiconductor substrate, and the nozzle support arm is rotated around the rotation axis of the semiconductor substrate in a direction opposite to the rotation direction of the semiconductor substrate, and from a plurality of chemical solution nozzles. It is characterized by discharging a chemical solution.

  According to a third aspect of the present invention, there is provided an apparatus for manufacturing a semiconductor device, comprising: a processing chamber in which a semiconductor substrate to be treated with a chemical solution is placed; and the semiconductor substrate is placed in the processing chamber and the semiconductor substrate is rotated in a predetermined direction. A chemical solution supply that simultaneously supplies a substrate support arm and a chemical solution having a predetermined processing temperature higher than normal temperature to a plurality of positions on the surface of the semiconductor substrate that is mounted on the substrate support arm and rotates in different diameter directions of the semiconductor substrate. Means.

  The semiconductor device manufacturing apparatus according to claim 4 is the semiconductor device manufacturing apparatus according to claim 3, wherein the chemical solution supply means is disposed above the substrate support arm and has a length corresponding to the diameter of the semiconductor substrate. A nozzle support arm and a plurality of chemical nozzles disposed on the lower surface of the nozzle support arm, the nozzle support arm rotating about the rotation axis of the rotating semiconductor substrate in a direction opposite to the rotation direction of the semiconductor substrate. The chemical solution is discharged from a plurality of chemical solution nozzles.

  According to the present invention, by supplying a high-temperature chemical solution simultaneously to a plurality of positions that are different in the diameter direction of the semiconductor substrate on the surface of the rotating semiconductor substrate, variations in the chemical temperature within the substrate surface are eliminated, Reaction uniformity within the substrate surface can be improved.

  Hereinafter, a semiconductor device manufacturing apparatus according to each embodiment of the present invention will be described with reference to the drawings. In each embodiment, a single wafer cleaning apparatus will be described as an example.

  In each of the following embodiments, a silicon oxide film formed from TEOS (tetraethoxysilane) is formed on the processing surface of a semiconductor substrate (wafer). While self-rotating the semiconductor substrate at 500 rpm or higher, a 50 ° C. HF chemical solution higher than the temperature in the clean room is applied to the processing surface (chemical solution treatment).

  A first embodiment of the present invention will be described with reference to FIG. This single wafer cleaning apparatus can hold the semiconductor substrate 1 on the substrate support arm 2 and rotate the semiconductor substrate 1 by rotating the substrate support arm 2 by the motor 6 (the same applies to the following embodiments). In the first embodiment, a resistance heating type heater 9 is arranged on the outer periphery of the processing chamber 3, the atmosphere in the processing chamber 3 is heated, and the entire semiconductor substrate 1 is equivalent to 50 ° C. which is the same as the chemical temperature (HF: 50 ° C.). Raise up to. Thereafter, when a chemical solution (HF: 50 ° C.) is applied from the chemical solution nozzle 4 onto the self-rotating (500 rpm or more) semiconductor substrate 1, the in-plane uniformity of the etching rate is improved to 2.29% as shown in FIG. Can be obtained. In FIG. 2, the wafer position (Wafer Position) on the horizontal axis indicates the distance from the center (0) to the end of the substrate 1 in the diametrical direction, and the etching rate (Etching Rate) on the vertical axis indicates the processing surface of the substrate 1. This is the etching rate of the silicon oxide film formed. The% uniformity value indicates that the smaller the numerical value, the higher the in-plane uniformity of the etching rate.

The uniformity in FIG. 2 is calculated as follows. The etching amount at each of 17 points in the wafer (substrate) plane is En (n = 1, 2, 3,..., 17), the maximum etching amount among 17 points is Emax, the minimum etching amount is Emin, and the average The value is Eave and the uniformity is Uni. When
Uni. [%] = [(Emax−Emin) / (2 · Eave)] × 100
However, Eave = (E1 + E2 + E3 +... + E17) / 17.

  Here, as a comparative example, in the method of FIG. 1 (first embodiment), the heater 9 is not provided and the semiconductor substrate 1 is not heated, and the other conditions are the same as those of the first embodiment. When the same semiconductor substrate 1 is treated with the same chemical solution (HF: 50 ° C.), the distribution of the etching rate in the substrate surface is as shown in FIG. 24 (shown in the same manner as FIG. 2). Since the temperature of the chemical solution on the substrate is different in each part such as a part, the etching rate is different (uniformity: 10.27%). In the present embodiment, by raising the temperature of the entire semiconductor substrate 1 in advance corresponding to the temperature of the chemical solution, it is possible to prevent a difference in the temperature of the chemical solution in the surface of the semiconductor substrate 1 and improve such non-uniformity.

  A second embodiment of the present invention will be described with reference to FIG. A microwave generator 11 is disposed on the side surface of the processing chamber 3. Prior to the chemical treatment, pure water mist is filled into the treatment chamber 3 from the pure water mist nozzle 12. The filled mist is irradiated with microwaves having a frequency of 2450 MHz from the microwave generator 11 to heat the atmosphere of the processing chamber 3 and the temperature of the substrate 1 is increased to a chemical temperature (HF: 50 ° C.). At this time, the temperature distribution in the chamber has an effect of making the temperature distribution uniform as compared with the case of performing the heating by the heater. FIG. 4A is a diagram showing the temperature distribution in the processing chamber 3 when heated using the microwave generator 11 of the second embodiment, and FIG. 4B is the first embodiment. FIG. 6 is a diagram showing a temperature distribution in the processing chamber 3 when heated by using a heater 9 in this case (in this case, since it is the first embodiment, the processing chamber 3 is not filled with pure water mist). The effects of the second embodiment can be confirmed.

  Thereafter, before the chemical treatment, the pure water mist is driven out of the treatment chamber 3 by the drain 10 and the chemical solution (HF: 50 ° C.) is applied from the chemical solution nozzle 4 onto the semiconductor substrate 1 that rotates (500 rpm or more). Prior to the chemical treatment, the temperature of the semiconductor substrate 1 is increased to the equivalent of the chemical temperature, so that the in-plane uniformity of the etching rate on the self-rotating substrate 1 during the treatment is displayed as shown in FIG. To 1.15%. In addition, in order to efficiently fill the processing chamber 3 with pure water mist, the processing chamber 3 can be depressurized in advance. Alternatively, the chamber 3 may be decompressed after the processing chamber 3 is filled with pure water mist. In this case, by depressurizing the pure water mist in the chamber 3, it is possible to quickly expel it from the chamber 3 and to volatilize the pure water attached to the side wall of the chamber 3 and the semiconductor substrate 1.

  A third embodiment of the present invention will be described with reference to FIG. A resistance heating type heater 9 is disposed on the outer periphery of the pretreatment chamber 14, the atmosphere in the chamber 14 is heated, and the entire semiconductor substrate 1 is raised to a temperature corresponding to a chemical solution temperature of 50 ° C. Thereafter, the substrate 1 is moved from the pretreatment chamber 14 to the treatment chamber 3 to perform chemical treatment. In this chemical treatment, when a chemical solution (HF: 50 ° C.) is applied from the chemical solution nozzle 4 onto the self-rotating (500 rpm or more) semiconductor substrate 1, the in-plane uniformity of the etching rate is shown in FIG. 7 (shown in the same manner as FIG. 2). Thus, it can be improved to 1.80%.

  A fourth embodiment of the present invention will be described with reference to FIG. A halogen lamp 15 is arranged on the outer periphery of the pretreatment chamber 14, the atmosphere in the chamber 14 is heated, and the entire semiconductor substrate 1 is raised to a chemical solution temperature equivalent to 50 ° C. Thereafter, the semiconductor substrate 1 is moved from the pretreatment chamber 14 to the treatment chamber 3 to perform chemical treatment. In this chemical treatment, when a chemical solution (HF: 50 ° C.) is applied from the chemical nozzle 4 onto the rotating substrate 1, the in-plane uniformity of the etching rate is 2.36 as shown in FIG. 9 (similar to FIG. 2). % Can be improved.

  A fifth embodiment of the present invention will be described with reference to FIG. The microwave generator 11 is disposed on the side surface of the pretreatment chamber 14. The pure water mist is filled in the chamber 14 from the pure water mist nozzle 12. The filled mist is irradiated with microwaves having a frequency of 2450 MHz from the microwave generator 11 to heat the atmosphere in the chamber 14 and to raise the temperature of the substrate 1 to a chemical solution processing temperature of 50 ° C. Thereafter, the substrate 1 is moved from the pretreatment chamber 14 to the treatment chamber 3 to perform chemical treatment. In this chemical treatment, when a chemical solution (HF: 50 ° C.) is applied from the chemical nozzle 4 onto the self-rotating (500 rpm or more) semiconductor substrate 1, the in-plane uniformity of the etching rate is shown in FIG. 11 (similar to FIG. 2). Thus, it can be improved to 2.91%. Moreover, in order to fill the chamber 14 with the pure water mist efficiently, the chamber 14 can be decompressed in advance. Alternatively, the chamber 14 may be decompressed after the pretreatment chamber 14 is filled with pure water mist. In this case, by depressurizing the pure water mist in the pretreatment chamber 14, it is possible to quickly expel it from the pretreatment chamber 14 and to volatilize the pure water deposited on the chamber side wall and the semiconductor substrate 1. .

  A sixth embodiment of the present invention will be described with reference to FIG. The temperature of pure water contained in the pure water tank 16 in the pretreatment chamber 14 is set in a range of 50 ± 5 ° C. with respect to the chemical solution temperature (HF: 50 ° C.). The semiconductor substrate 1 is inserted into the pure water tank 16 in the pretreatment chamber 14, and the entire substrate 1 is raised to a chemical temperature equivalent to 50 ° C. Thereafter, the substrate 1 is moved from the chamber 14 to the processing chamber 3 to perform chemical treatment. In this chemical treatment, when a chemical solution (HF: 50 ° C.) is applied from the chemical solution nozzle 4 onto the semiconductor substrate 1 that rotates by itself (500 rpm or more), the in-plane uniformity of the etching rate is shown in FIG. 13 (similar to FIG. 2). Thus, it can be improved to 3.48%.

  In the above third to sixth embodiments, by heating the semiconductor substrate 1 using the pretreatment chamber 14, it is not necessary to raise the temperature of the semiconductor substrate 1 before chemical treatment in the treatment chamber 3. Therefore, the time can be shortened.

  A seventh embodiment of the present invention will be described with reference to FIG. By disposing a resistance heating type heater 9 directly under the substrate support arm 2, the temperature can be easily controlled directly from the back surface of the semiconductor substrate 1, and the entire substrate 1 is raised to a temperature corresponding to a chemical solution temperature of 50 ° C. Thereafter, when a chemical solution (HF: 50 ° C.) is applied from the chemical solution nozzle 4 onto the self-rotating (500 rpm or more) semiconductor substrate 1, the in-plane uniformity of the etching rate is shown in FIG. 15 (shown in the same manner as FIG. 2). To 1.66%.

  An eighth embodiment of the present invention will be described with reference to FIG. By disposing the halogen lamp 15 directly under the substrate support arm 2, it becomes easy to control the temperature directly from the back surface of the semiconductor substrate 1, and the entire substrate 1 is raised to a chemical temperature equivalent to 50 ° C. Thereafter, when a chemical solution (HF: 50 ° C.) is applied from the chemical solution nozzle 4 onto the self-rotating (500 rpm or more) semiconductor substrate 1, the in-plane uniformity of the etching rate is shown in FIG. 17 (shown in the same manner as FIG. 2). It can be improved to 1.10%.

  A ninth embodiment of the present invention will be described with reference to FIG. The substrate support arm 2 is a flat plate type parallel to the semiconductor substrate 1, and is provided with a pure water nozzle 21 that discharges high-temperature pure water from the center of the substrate support arm 2. The temperature of pure water discharged from the pure water nozzle 21 is set in a range of 50 ± 5 ° C. with respect to the chemical temperature (HF: 50 ° C.). The space between the arm 2 and the substrate 1 is filled with the high-temperature pure water discharged from the pure water nozzle 21 so that the temperature can be easily controlled directly from the back surface of the substrate 1. Raise. Thereafter, when a chemical solution (HF: 50 ° C.) is applied from the chemical solution nozzle 4 onto the self-rotating (500 rpm or more) semiconductor substrate 1, the in-plane uniformity of the etching rate is shown in FIG. 19 (shown in the same manner as FIG. 2). It can be improved to 2.81%.

A tenth embodiment of the present invention will be described with reference to FIG. The substrate support arm 2 is a flat plate type parallel to the semiconductor substrate 1, and is provided with an N ₂ nozzle 22 that discharges high-temperature N ₂ gas from the center of the substrate support arm 2. The temperature of the N ₂ gas discharged from the N ₂ nozzle 22 is set in a range of 50 ± 5 ° C. with respect to the chemical solution temperature (HF: 50 ° C.). The high temperature N ₂ discharged from the N ₂ nozzle 22 fills the space between the arm 2 and the substrate 1 and makes it easy to control the temperature directly from the back surface of the substrate 1. Raise. Thereafter, when a chemical solution (HF: 50 ° C.) is applied from the chemical solution nozzle 4 onto the self-rotating (500 rpm or more) semiconductor substrate 1, the in-plane uniformity of the etching rate is displayed as shown in FIG. It can be improved to 3.35%.

  In the first to tenth embodiments described above, the chemical liquid (HF: 50 ° C.) heated to a high temperature by a heating means (not shown) outside the processing chamber 3 is used for the chemical liquid treatment. The nozzle 4 discharges toward the center of the semiconductor substrate 1.

  18 and 20, the substrate 1 is shown as floating, but the wafer (substrate 1) is fixed by a (chuck) pin that makes point contact with the wafer bevel portion. There are three or more pins on the substrate support arm 2 (not shown).

  An eleventh embodiment of the present invention will be described with reference to FIG. FIG. 22B is a view from above of the chemical nozzle support arm 18 of FIG. The chemical nozzle support arm 18 has an arm length corresponding to the diameter of the semiconductor substrate 1, and a plurality of chemical nozzles 4 are disposed on the lower surface of the arm 18. The chemical nozzle support arm 18 is rotated in a direction 19 opposite to the rotation direction 20 of the substrate 1 and the substrate support arm 2 on the semiconductor substrate 1 that rotates itself (500 rpm or more) with the position of the central portion of the substrate 1 as the rotation axis. By applying the chemical liquid (HF: 50 ° C.) from the chemical nozzle 4 while rotating itself, there is no difference in the chemical temperature on the surface of the substrate 1, and the in-plane uniformity of the etching rate is the same as in FIG. Can be improved to 1.73%.

  In the eleventh embodiment, the chemical liquid (HF: 50 ° C.) heated to a high temperature by a heating means (not shown) outside the processing chamber 3 passes through the chemical liquid line 17 during the chemical liquid treatment. The plurality of chemical liquid nozzles 4 are discharged onto the semiconductor substrate 1.

  Further, as in the eleventh embodiment, the in-plane uniformity of the etching rate can be further improved by rotating the chemical liquid nozzle support arm 18, but it is conventionally possible without rotating the chemical liquid nozzle support arm 18. Can be improved. Further, a chemical solution in which a plurality of linear chemical solution nozzle support arms 18 are crossed on the rotation axis of the substrate 1 instead of rotating, instead of the linear chemical solution nozzle support arm 18 as shown in FIG. A nozzle support arm may be used. For example, two linear chemical liquid nozzle support arms 18 may be crossed in a cross shape and may not rotate.

  In each embodiment, it goes without saying that the number of rotations of the substrate, the type / temperature of the chemical solution, the film quality / temperature of the substrate, the frequency of the microwave, and the type of the heater / lamp are not limited to those described above.

  The method and apparatus for manufacturing a semiconductor device of the present invention have the effect of eliminating variations in the temperature of the chemical solution in the substrate surface and improving the reaction uniformity in the substrate surface with the chemical solution. It is useful as a wet processing apparatus generally used in the manufacturing process, particularly as a semiconductor substrate cleaning apparatus.

Sectional drawing which shows the washing | cleaning apparatus of the 1st Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of the 1st Embodiment of this invention. Sectional drawing which shows the washing | cleaning apparatus of the 2nd Embodiment of this invention. The figure which shows the effect by the microwave heating of the 2nd Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of the 2nd Embodiment of this invention. Sectional drawing which shows the washing | cleaning apparatus of the 3rd Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of the 3rd Embodiment of this invention. Sectional drawing which shows the washing | cleaning apparatus of the 4th Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of the 4th Embodiment of this invention. Sectional drawing which shows the washing | cleaning apparatus of the 5th Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of the 5th Embodiment of this invention. Sectional drawing which shows the washing | cleaning apparatus of the 6th Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of the 6th Embodiment of this invention. Sectional drawing which shows the washing | cleaning apparatus of the 7th Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of the 7th Embodiment of this invention. Sectional drawing which shows the washing | cleaning apparatus of the 8th Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of the 8th Embodiment of this invention. Sectional drawing which shows the washing | cleaning apparatus of the 9th Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of the 9th Embodiment of this invention. Sectional drawing which shows the washing | cleaning apparatus of the 10th Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of the 10th Embodiment of this invention. (A) is sectional drawing which shows the washing | cleaning apparatus of the 11th Embodiment of this invention, (b) is a top view which shows the chemical | medical solution nozzle support arm. The distribution map which shows the etching rate in the wafer surface of the 11th Embodiment of this invention. The distribution map which shows the etching rate in the wafer surface of a comparative example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor substrate 2 Substrate support arm 3 Processing chamber 4 Chemical solution nozzle 5 Rotating shaft 6 Motor 7 N ₂ nozzle 8 Pure water nozzle 9 Heater 10 Drain 11 Microwave generator 12 Pure water mist nozzle 13 Temperature zone notation 14 Preprocessing chamber 15 Lamp 16 Pure water tank 17 Chemical liquid line 18 Chemical liquid nozzle support arm 19 Rotating direction of arm 18 Rotating direction of arm 2 21 Pure water nozzle 22 N ₂ gas nozzle

Claims (4)

A method of manufacturing a semiconductor device for chemical processing a semiconductor substrate by supplying a chemical to the surface of the semiconductor substrate,
A semiconductor device characterized in that, while rotating the semiconductor substrate, the chemical solution having a predetermined processing temperature higher than normal temperature is simultaneously supplied to a plurality of positions on the surface of the semiconductor substrate and different in the diameter direction of the semiconductor substrate. Manufacturing method.   A nozzle support arm in which a plurality of chemical nozzles for discharging a chemical liquid at the processing temperature is arranged corresponding to a plurality of positions different in the diameter direction of the semiconductor substrate is disposed above the semiconductor substrate, and the nozzle support arm is 2. The method of manufacturing a semiconductor device according to claim 1, wherein the chemical solution is discharged from the plurality of chemical solution nozzles while rotating in a direction opposite to a rotation direction of the semiconductor substrate around a rotation axis of the semiconductor substrate. . A processing chamber for placing therein a semiconductor substrate to be treated with a chemical solution;
A substrate support arm for placing the semiconductor substrate in the processing chamber and rotating the semiconductor substrate in a predetermined direction;
A chemical supply means for simultaneously supplying a chemical solution having a predetermined processing temperature higher than normal temperature to a plurality of positions on the surface of the semiconductor substrate which are placed on the substrate support arm and rotate and which are different in the diameter direction of the semiconductor substrate; A device for manufacturing a semiconductor device. The chemical solution supply means includes a nozzle support arm disposed above the substrate support arm and having a length corresponding to the diameter of the semiconductor substrate, and a plurality of chemical solution nozzles disposed on the lower surface of the nozzle support arm,
4. The chemical solution is ejected from the plurality of chemical solution nozzles while the nozzle support arm rotates about a rotation axis of the rotating semiconductor substrate in a direction opposite to a rotation direction of the semiconductor substrate. The manufacturing apparatus of the semiconductor device as described in 2. above.

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