JP2008028177A - Apparatus for heating substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for heating substrates for uniformizing the temperature distribution of a substrate that is subjected to heat processing. <P>SOLUTION: A heating means 12 is provided to a wall 2b of at least a lower cover 2, in the lower cover 2, and an upper cover 3 constituting an apparatus for processing substrates 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a substrate heating apparatus that heats a substrate, and more particularly to a substrate heating apparatus used in photolithography of a semiconductor wafer or liquid crystal glass in a manufacturing process of a semiconductor element or a liquid crystal panel.

  In photolithography, which is one of the manufacturing processes of a semiconductor element or a liquid crystal panel, a photoresist heating process (for a semiconductor wafer or a glass for liquid crystal) is performed on a substrate 6 using a substrate heating apparatus 1 as shown in FIG. PAB: Post-Applied Bake and PEB: Post-Exposure Bake) are performed.

  At this time, in order to form an accurate pattern on the substrate surface, it is necessary to make the temperature distribution of the substrate 6 uniform. However, since the substrate 6 is heated from below by the heater 8 through the heating plate 9, There is a problem that temperature unevenness occurs in the substrate 6 due to a difference in the amount of heat radiation to the side of the edge portion.

  In order to solve such a problem, Patent Document 1 discloses an invention in which a heater is divided into a plurality of regions and the temperature of each region is controlled based on a temperature sensor.

However, the invention described in Patent Document 1 has a problem that it is difficult to make the temperature distribution of the substrate more uniform because thermal interference occurs between the heater regions.
JP 2004-134723 A

  The present invention has been made in view of such problems, and an object of the present invention is to provide a substrate heating apparatus that can make the temperature distribution of the substrate more uniform.

  In order to achieve the above object, the present invention provides a substrate heating apparatus that heats a substrate placed on a heating body in a processing container including an upper cover and a lower cover, wherein the lower cover includes It consists of a bottom plate for holding the heating body and a wall portion standing around the bottom plate and surrounding the heating body, and a heating means is provided on the wall portion.

  And when the upper cover in said board | substrate heating apparatus consists of a top plate and the wall part suspended around the said top plate, a heating means can also be provided in the said suspended wall part. desirable.

  As the heating means, a metal foil heater or a sheathed heater is preferably used.

  According to the present invention, there is provided a substrate heating apparatus that heat-treats a substrate placed on a heating body in a processing container including an upper cover and a lower cover, wherein the lower cover is a bottom plate that holds the heating body. And a wall heating device that is provided around the bottom plate and surrounds the heating element, since the heating means is provided on the wall, heat release from the edge of the substrate is suppressed, and heat interference Therefore, the temperature distribution of the substrate can be made more uniform.

  Further, in the case where the upper cover is composed of a top plate and a wall portion suspended around the top plate, since the heating means is also provided on the suspended wall portion, heat from the outside of the processing container is provided. By eliminating the influence, the temperature distribution of the substrate can be made more uniform.

  Embodiments of the present invention will be described below with reference to the drawings.

  A substrate heating apparatus according to a first embodiment of the present invention is shown in FIG.

  The substrate heating apparatus 1 heats a substrate 6 placed on a substrate heating body 5 in a processing container 4 composed of a lower cover 2 and an upper cover 3.

  The lower cover 2 has a structure in which a wall portion 2b is erected around the bottom plate 2a, and the upper cover 3 has a structure in which a wall portion 3b is erected around the top plate 3a, both of which are thermally conductive. Made from excellent materials such as aluminum or stainless steel. The processing container 4 is configured by connecting the lower cover 2 and the upper cover 3 via an O-ring 7 so that the concave portions thereof face each other.

  The substrate heating body 5 has a structure in which a heater 8 is sandwiched between a heating plate 9 and a holding plate 10 from above and below, and is held by a plurality of support pins 11 arranged concentrically on the bottom plate 2a of the lower cover 2, The side surface is surrounded by the wall 2b at a constant interval.

  On the wall 2b of the lower cover 2, a heater 12 as a heating means is installed. The heater 12 is obtained by winding a metal foil heater or a sheathed heater on the outer peripheral surface of the wall 2b, and is fixed to the lower cover 2 by being tightened by a fixing ring 14 from the outside via a heat insulating material 13. Yes. As the material of the heat insulating material 13, for example, felt, Teflon sheet, quartz wool, or silica fiber can be used. The fixing method of the heater 12 is not limited to such mechanical means, and may be directly affixed or welded on the outer peripheral surface of the wall 2b, or a combination thereof.

  In such a configuration, the substrate 6 placed on the substrate heating body 5 is heated from below by the heater 8, and an edge portion where heat dissipation is larger than that of the central portion is interposed through the wall portion 2 b. Heating from the side by the heater 12 suppresses heat dissipation and reduces thermal interference, so that the temperature distribution of the substrate 6 can be made more uniform.

  As shown in FIG. 2, the heater 12 may be divided into a plurality of parts in the circumferential direction, and the temperature distribution of the substrate 6 can be made uniform with high accuracy by adjusting the amount of generated heat. . In FIG. 2, the heater 12 is divided into six in the circumferential direction, but the number is not necessarily limited.

  FIG. 3 shows a substrate heating apparatus according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same part as FIG. 1, and the description is abbreviate | omitted.

  In the substrate heating apparatus 1 according to the present embodiment, a heater 15 as a heating unit is provided on the wall 3b of the upper cover 3 in the first embodiment. As in the case of the heater 12 in the lower cover 2, the heater 15 is obtained by winding a metal foil heater or a sheathed heater on the outer peripheral surface of the wall 3 b, and a fixing ring 17 from the outside via a heat insulating material 16. It is fixed to the upper cover 3 by tightening. Of course, the heater 15 may also be directly affixed or welded onto the outer peripheral surface of the wall 3 b, or may be fixed by a combination of them and the fixing ring 17.

  In such a configuration, heat release from the edge portion of the substrate 6 is suppressed by side heating by the two heaters 12 and 15 and heat influence from the outside of the processing container 4 is eliminated. Therefore, the temperature distribution of the substrate 6 can be made more uniform than in the case of the first embodiment.

  The heater 15 of the upper cover 3 can also be divided into a plurality of parts in the circumferential direction as in the example shown in FIG. 2, and the substrate can be adjusted by adjusting the amount of heat generated in combination with the divided heaters 12. 6 can be made uniform with high accuracy.

  In the two embodiments described above, when a semiconductor wafer is taken as an example of the substrate 6, the cross section of the substrate heating apparatus 1 is circular as shown in FIG. 2, but is rectangular when liquid crystal glass is used as the substrate. Needless to say.

It is sectional drawing of the substrate heating apparatus which concerns on the 1st Embodiment of this invention. It is sectional drawing of the AA arrow shown in FIG. It is sectional drawing of the substrate heating apparatus which concerns on the 2nd Embodiment of this invention. It is sectional drawing of the conventional board | substrate heating apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate heating apparatus 2 Lower cover 2a Bottom plate 2b Wall part 3 Upper cover 3a Top plate 3b Wall part 4 Processing container 5 Substrate heating body
6 Substrate 7 O-ring 8 Heater
9 Heating plate 10 Presser plate 11 Support pin
12 Heater for lower cover 13 Heat insulating material for lower cover 14 Fixing ring 15 for lower cover Heating heater for upper cover 16 Heat insulating material for upper cover 17 Fixing ring for upper cover

Claims (3)

A substrate heating apparatus for heat-treating a substrate placed on a heating body in a processing container composed of an upper cover and a lower cover,
The lower cover is composed of a bottom plate that holds the heating body, and a wall that stands around the bottom plate and surrounds the heating body,
The substrate heating apparatus which provided the heating means in the said wall part. The upper cover is composed of a top plate and a wall portion suspended around the top plate,
The substrate heating apparatus according to claim 1, wherein heating means is provided on the suspended wall portion. The substrate heating apparatus according to claim 1, wherein the heating unit is a metal foil heater or a sheathed heater.

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