JP2007048814A - Substrate holding device, semiconductor manufacturing apparatus and method of manufacturing semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate holding device which can surely prevent infiltration of chemicals to the rear surface of a substrate, and to provide a semiconductor manufacturing apparatus. <P>SOLUTION: A substrate 3 is sucked and held on a substrate holder 11A provided on a rotary shaft 10B. A gas jetting port 12B communicating with a gas supply passage 12A is provided on the side wall of the substrate holder 11A. The gas jetting port 12B is extended at an angle of α against the horizontal direction so that it may face the rear surface of the substrate 3. Before a resist 4 is supplied from a nozzle 5, an inert gas supplied from an inert gas supply 6 is jetted from the gas jetting port 12B to the rear surface of the substrate through the gas supply passage 12A. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a semiconductor manufacturing apparatus that performs processing involving rotation of a substrate such as resist coating and wet etching, and more particularly to a substrate holding apparatus that holds a substrate by suction.

A spin coating method is known as a method for uniformly and thinly applying a chemical solution such as a photoresist (hereinafter abbreviated as “resist”), a developing solution, and an etching solution on a semiconductor substrate or a glass substrate. A resist coating apparatus is known as an example of a semiconductor manufacturing apparatus that executes this spin coating method. In the resist coating apparatus, a vacuum suction stand is disposed as a substrate holding device for sucking and holding the substrate.
In a resist coating apparatus, after a resist is dropped on a substrate held on a vacuum suction table, the substrate is rotated. Excess resist is scattered from the outer periphery of the substrate by the centrifugal force generated by the rotation. In this way, the resist film can be uniformly applied on the substrate with a desired thickness.

By the way, the vacuum suction table does not rotate immediately after the resist is dropped. Further, the rotation speed is low immediately after the vacuum suction table starts to rotate. Therefore, depending on the surface treatment state of the substrate and the viscosity and type of the resist, as shown in FIG. 6, the resist rotates around the back surface of the substrate 3 held by suction on the vacuum suction table 30 due to the surface tension of the resist 4. There was a case. The resist that wraps around the back surface of the substrate is not blown away by the centrifugal force and remains even after the resist coating process is completed. This resist on the backside of the substrate may cause generation of particles. Furthermore, in an exposure apparatus that is transported after resist coating, the substrate is not parallel to the photomask, leading to a reduction in exposure accuracy.
In addition, the resist that has entered the back surface of the substrate may reach the suction surface of the vacuum suction table. In this case, the suction surface and the substrate are bonded to each other by the resist, and the substrate cannot be removed after the resist is applied. Further, when the resist is sucked into the vacuum suction groove formed on the suction surface, the groove is clogged and the suction power of the substrate is reduced.

  In order to solve these problems, an apparatus for ejecting gas to the back surface of the substrate has been disclosed (for example, see Patent Document 1).

JP-A-7-78743 (FIG. 1)

  However, in the apparatus 31 according to Patent Document 1, gas is ejected from the ejection port 31A in parallel to the back surface of the substrate 3, as shown in FIG. For this reason, a vacuum region (negative pressure region) E is formed by the Bernoulli effect caused by the gas flow D. As a result, the resist 4 is attracted to the back surface of the substrate 3 on the contrary, and there is a problem that it is not possible to reliably prevent the resist from wrapping around the back surface of the substrate.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a substrate holding device and a semiconductor manufacturing apparatus that can reliably prevent a chemical solution from flowing into the back surface of the substrate.

A substrate holding device according to the present invention is a substrate holding device that holds a substrate by suction,
A rotation axis;
A substrate holding part provided on the rotating shaft and holding the substrate on the upper surface;
A gas supply passage provided in communication with the rotary shaft and the substrate holding portion;
A gas jet port communicating with the gas supply passage, wherein the gas jet port is formed on the side wall of the substrate holding portion at an angle facing the back surface of the substrate. .

A semiconductor manufacturing apparatus according to the present invention is a semiconductor manufacturing apparatus having the substrate holding apparatus,
A gas supply unit for supplying an inert gas to the gas supply passage;
A chemical solution supply unit that supplies a chemical solution to the surface of the substrate held on the upper surface of the substrate holding unit is provided.

  As described above, according to the present invention, it is possible to reliably prevent the chemical solution from flowing to the back surface of the substrate by ejecting the inert gas from the gas jet port provided on the side wall of the substrate holding portion to the back surface of the substrate.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof may be simplified or omitted.

Embodiment 1 FIG.
FIG. 1 is an external view for explaining a substrate holding apparatus according to Embodiment 1 of the present invention. 2 is a cross-sectional view taken along the line AA ′ of the substrate holding device shown in FIG.

  As shown in FIGS. 1 and 2, the substrate suction stand as the substrate holding device 1 includes a rotating shaft 10B and a substrate holding portion 10A provided on the rotating shaft 10B. The substrate holding part 10A and the rotating shaft 10B are integrally formed. The rotating shaft 10 </ b> B is connected to the motor 2. Therefore, the rotating shaft 10 </ b> B is configured to be rotatable by driving the motor 2.

  Grooves 11 </ b> B are formed on the surface of the substrate holding unit 10 </ b> A, that is, on the suction surface for vacuum suction of the substrate. An exhaust passage 11A is formed in the substrate holding portion 10A and the rotating shaft 10B. One end of the exhaust passage 11A communicates with the groove 11B, and the other end of the exhaust passage 11A is connected to a vacuum source (not shown). The vacuum source is, for example, a vacuum pump or a factory exhaust line.

  A gas supply passage 12A is formed inside the substrate holding part 10A and the rotating shaft 10B. A plurality of gas supply passages 12A are formed around the exhaust passage 11A. As shown in FIG. 2, in the substrate holding part 10A, the gas supply passage 12A extending in the vertical direction is bent toward the outer peripheral direction. The tip of the bent gas supply passage 12A communicates with the gas ejection port 12B. That is, the gas ejection port 12B communicating with the gas supply passage 12A is formed on the side wall of the substrate holding portion 10A. The other end of the gas supply passage 12A is connected to an inert gas supply unit (described later). The inert gas supply unit is connected to, for example, a gas cylinder filled with an inert gas or an inert gas line of a factory. Thereby, inert gas, such as nitrogen gas and argon gas, can be ejected from the gas ejection port 12B at a desired time.

  As shown in FIG. 2, the gas outlet 12 </ b> B is formed so as to face upward by an angle α with respect to the horizontal direction. Thereby, an inert gas is ejected in the direction shown by arrow B in the figure. That is, an inert gas is ejected from the gas ejection port 12B toward the outer periphery of the back surface of the substrate held by the substrate holding unit 10A (described later). According to the experiments by the present inventors, when the angle α of the gas ejection port 12B is set to 30 to 60 degrees, it is possible to effectively prevent the chemical solution from flowing around the back surface of the substrate.

FIG. 3 is a diagram illustrating a formation position of the gas ejection port 12B.
As shown in FIG. 3, a plurality of gas ejection ports 12B are provided radially. That is, a plurality of gas ejection ports 12B are formed over the entire side wall of the substrate holding portion 10A. In the example shown in FIG. 3, 16 gas outlets 12B are formed at equal intervals. Thereby, as shown by the arrow B in the figure, the inert gas can be ejected uniformly to the outer periphery of the back surface of the substrate 3.

  The operation of the substrate holding apparatus will be described in a second embodiment to be described later.

  As described above, in the first embodiment, the gas ejection port 12B extending upward by the angle α with respect to the horizontal direction is provided on the side wall of the substrate holding unit 10A. Thereby, an inert gas can be supplied to the back surface of the substrate 3 held on the substrate holding part 10A. Furthermore, it is possible to prevent the generation of a vacuum region due to the Bernoulli effect as occurred in the above-described prior art during the gas supply. Accordingly, it is possible to obtain the substrate holding device 1 that can reliably prevent the chemical solution from flowing to the back surface of the substrate.

In the first embodiment, as shown in FIG. 3, the shape of the gas outlet 12B is such that the opening area on the outer peripheral side is smaller than the opening area on the center side. It may be an opening that is always constant. That is, the gas outlet 12B may be a cylindrical opening.
Furthermore, as shown in FIG. 4, the shape of the gas ejection port 12 </ b> B can be a shape in which the opening area on the outer peripheral side is larger than the opening area on the center side. For example, the shape of the gas outlet 12 </ b> B can be a fan-shaped opening whose outer peripheral side is wide open. In this case, as shown in FIG. 4, an inert gas can be ejected in a wide range from one gas ejection port 12B. Therefore, the number of gas ejection ports 12B can be reduced, and the structure of the substrate holding device can be simplified.

  Further, in the first embodiment, the substrate holding unit 10A and the rotating shaft 10B are configured integrally, but may be configured separately.

Embodiment 2. FIG.
In the second embodiment of the present invention, a semiconductor manufacturing apparatus having the substrate holding apparatus of the first embodiment will be described. Specifically, a resist coating apparatus will be described.

FIG. 5 is a schematic diagram for explaining a semiconductor manufacturing apparatus according to the second embodiment of the present invention.
As shown in FIG. 5, the resist coating apparatus as the semiconductor manufacturing apparatus 20 includes a substrate holding apparatus 1. A nozzle 5 is disposed above the substrate holding device 1. The nozzle 5 is configured to supply a resist 4 as a chemical solution on the surface of the substrate 3.

  As described in the first embodiment, the gas supply passage 12A is formed in the substrate holding portion 10A and the rotating shaft 10B constituting the substrate holding apparatus 1. A gas outlet 12B communicating with the gas supply passage 12A is formed on the side wall of the holding portion 10A. The gas outlet 12B is formed so as to face the back surface of the substrate 3, and more specifically, is formed so as to extend upward by an angle α (for example, 30 to 60 degrees) with respect to the horizontal direction. Yes. The gas supply passage 12 </ b> A is connected to the inert gas supply unit 6. The inert gas supply unit 6 is configured to be able to supply an inert gas such as nitrogen gas or argon gas. The inert gas supply unit 6 is, for example, a gas cylinder or an inert gas line in a factory where the semiconductor manufacturing apparatus is installed.

  The semiconductor manufacturing apparatus shown in FIG. 5 includes a solvent vapor supply unit 7. The solvent vapor supply unit 7 is configured to generate a vapor of the solvent contained in the resist (hereinafter referred to as “solvent vapor”). The solvent vapor supply unit 7 includes, for example, a container for containing a solvent and a heating mechanism such as a heater for heating the container. The solvent vapor generated by the solvent vapor supply unit 7 is contained in the inert gas supplied from the inert gas supply unit 6 as necessary (for example, by switching control of a valve (not shown)). That is, an inert gas containing solvent vapor can be ejected from the gas ejection port 12B.

  Next, the operation of the semiconductor manufacturing apparatus will be described with reference to FIG. That is, a method for manufacturing a semiconductor device, more specifically, a method for forming a resist film will be described.

  First, the substrate 3 is placed on the upper surface of the substrate holding unit 10A by a transfer robot (not shown). Next, air in the exhaust passage 11A and the groove 11B is exhausted by a vacuum pump or the like, thereby forming a vacuum state between the back surface of the substrate 3 and the upper surface of the substrate holding portion 10A. Thereby, the substrate 3 is vacuum-sucked on the substrate holding part 10A.

Next, nitrogen gas is supplied from the inert gas supply unit 6 into the gas supply passage 12A, and nitrogen gas is ejected from the gas ejection port 12B at a desired flow rate. For example, the supply pressure of the inert gas is 3 × 10 ⁵ Pa, and the flow rate is 2000 sccm.

  Subsequently, a resist 4 is dropped on the substrate 3 from the nozzle 5. At this time, the substrate holding portion 10A and the rotating shaft 10B have not yet rotated, but the nitrogen gas ejected from the gas outlet 12B to the back surface of the substrate 3 reliably prevents the resist 4 from entering the back surface of the substrate 3. Can do.

  Next, by driving the motor 2 and rotating the rotary shaft 10B, the substrate holding portion 10A and the vacuum-adsorbed substrate 3 are rotated. For example, the rotation speed of the substrate 3 is 3000 rpm. Thereby, unnecessary resist 4a is scattered in the substrate outer peripheral direction by the centrifugal force C. As a result, a thin and uniform resist film is formed on the substrate 3. Immediately after the start of rotation, the rotation speed is low, but the nitrogen gas ejected from the gas outlet 12B to the back surface of the substrate 3 can surely prevent the resist 4 from wrapping around the back surface of the substrate 3.

  Thereafter, the motor 2 is stopped and the rotation of the substrate 3 is stopped, and then the supply of nitrogen gas by the inert gas supply unit 6 is stopped.

As described above, in the second embodiment, the gas injection port 12B extending toward the back surface of the substrate 3 is provided on the side wall of the substrate holding unit 10A. Then, before supplying the chemical solution to the substrate surface, an inert gas was ejected to the back surface of the substrate 3 through the gas injection port 12B. Since the inert gas is injected at a predetermined angle with respect to the back surface of the substrate, the formation of a vacuum region due to the Bernoulli effect as occurs in the prior art does not occur. Therefore, it is possible to reliably prevent the resist from wrapping around the back surface of the substrate 3 even before the substrate 3 is rotated (that is, when the rotation is stopped) and at a low rotation. There is no need to clean the back surface of the substrate 3, and the manufacturing cost can be reduced.
In addition, since no resist film is formed on the back surface of the substrate, the photomask and the substrate can be paralleled with high accuracy during the subsequent exposure, and the exposure can be performed with high accuracy. Furthermore, resist inflow into the groove 11B of the substrate holding part 10A can be prevented. Therefore, the semiconductor manufacturing apparatus can be operated stably.

  By the way, depending on the type of the resist 4, the scattered resist 4a may become mist and adhere to the vicinity of the outer periphery of the back surface of the substrate 3. In addition, there may be a case where it is desired to actively clean the vicinity of the outer periphery. Although it is conceivable to use a cleaning liquid, it is not preferable because the manufacturing cost increases. In such a case, the inert gas supplied from the inert gas supply unit 6 can contain the solvent vapor supplied from the solvent vapor supply unit 7. That is, an inert gas containing solvent vapor can be ejected from the gas ejection port 12B. Thereby, the cleaning effect of the back surface of the substrate 3 can be obtained simultaneously.

  In the second embodiment, the resist coating apparatus has been described. However, the present invention is also applied to a semiconductor manufacturing apparatus that performs processing involving rotation of a substrate, such as a resist developing apparatus or a wet etching apparatus. Can do. Also in this case, it is possible to reliably prevent the chemical solution from flowing around the back surface of the substrate.

  In addition, the number, shape, and angle of the gas ejection ports 12B, the pressure and flow rate of the inert gas, and the like can be appropriately changed according to the viscosity of the chemical solution (resist etc.) to be used and the substrate rotation speed.

It is an external view for demonstrating the board | substrate holding device by Embodiment 1 of this invention. It is A-A 'sectional drawing of the board | substrate holding | maintenance apparatus shown in FIG. It is a figure which shows the formation position of a gas jet nozzle. It is a figure which shows the modification of the shape of a gas jet nozzle. It is the schematic for demonstrating the semiconductor manufacturing apparatus by Embodiment 2 of this invention. It is a figure which shows the wraparound of the resist to the substrate back surface. It is a figure for demonstrating the vacuum area | region formed by the Bernoulli effect in the conventional apparatus.

Explanation of symbols

    DESCRIPTION OF SYMBOLS 1 Substrate holding device, 2 Motor, 3 Substrate, 4 Resist, 5 Nozzle, 6 Inert gas supply part, 7 Solvent vapor supply part, 10A Substrate holding part, 10B Rotating shaft, 11A Exhaust passage, 11B Groove, 12A Gas supply passage 12B Gas outlet.

Claims (7)

A substrate holding device for sucking and holding a substrate,
A rotation axis;
A substrate holding part provided on the rotating shaft and holding the substrate on the upper surface;
A gas supply passage provided in communication with the rotary shaft and the substrate holding portion;
A substrate holding apparatus comprising: a gas jet port communicating with the gas supply passage, wherein the gas jet port is formed on the side wall of the substrate holding portion at an angle facing the back surface of the substrate. . The substrate holding apparatus according to claim 1,
The gas ejection port is formed so that an opening area on the outer peripheral side is larger than an opening area on the center side of the substrate holding part. The substrate holding apparatus according to claim 2, wherein
The gas ejection port has a fan shape, and is a substrate holding device. In the board | substrate holding | maintenance apparatus in any one of Claim 1 to 3,
A substrate holding apparatus, wherein a plurality of the gas ejection ports are formed at equal intervals. A semiconductor manufacturing apparatus having the substrate holding device according to claim 1,
A gas supply unit for supplying an inert gas to the gas supply passage;
A semiconductor manufacturing apparatus comprising: a chemical solution supply unit configured to supply a chemical solution to the surface of the substrate held on the upper surface of the substrate holding unit. The semiconductor manufacturing apparatus according to claim 5,
A semiconductor manufacturing apparatus, further comprising: a solvent vapor supply unit that generates a vapor of the solvent contained in the chemical solution and causes the generated vapor to be contained in the inert gas supplied from the gas supply unit. A semiconductor device manufacturing method using the semiconductor manufacturing device according to claim 5.

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