JPH08227882A - Wafer baking device - Google Patents

Abstract

PURPOSE: To realize a wafer baking device which is very uniform in temperature distribution throughout its surface by a method wherein two thermally conductive members are formed like a disk conforming to the shape of a wafer respectively, a heat pipe is symmetrically buried in the joint surface of each of the conductive members in a radial manner, the conductive members are joined together making their joint surfaces confront each other, and a heating member is provided to underside of the joined conductive members for the formation of a wafer baking device, wherein a wafer is placed on its surface for baking. CONSTITUTION: Material excellent in thermal conductivity is formed into a disklike thermal conductive member 2 conforming to the shape of a wafer, a heat pipe 1 is symmetrically buried in the joint surface of each of the conductive member 2 in a radial manner, the two conductive members 2 are joined together making their joint surfaces confront each other, and a heating member 3 is provided to underside of the joined conductive members 2 for the formation of a wafer baking device, wherein a wafer is placed on its surface for baking. By this setup, when heat released from the heating member 3 is conducted to a part of the heat pipe 1, heat is quickly and uniformly transmitted to all the thermal conductive members 2 by the heat conducting action of the heat pipes 1, so that all the thermal conductive members 2 are evenly heated almost uniform in temperature distribution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer printing apparatus for forming semiconductor devices such as ICs.

[0002]

2. Description of the Related Art A semiconductor device such as an IC (integrated circuit) is subjected to photolithography for forming a pattern on a highly pure silicon single crystal wafer by exposure to a photosensitive resin, followed by thermal oxidation and impurities. It is formed through various work processes such as diffusion, ion implantation, etching, vapor phase growth, metal deposition and the like.

Of these, a baking apparatus as shown in FIG. 5, for example, is known in order to oxidize the wafer by heating during the thermal oxidation step. That is, this printing apparatus includes a disc-shaped aluminum plate 100 that matches the shape of a wafer (not shown),
The heater 10 fixed to the back surface of the aluminum plate 100
1, the heat generated from the heater 101 is propagated to the aluminum plate 100 having good thermal conductivity on which the wafer is mounted, and the wafer is thermally oxidized.

[0004]

However, in this printing apparatus, even if the heat generated from the heater is uniform in each part, the aluminum plate through which this heat is conducted dissipates to the outside from the shape of the aluminum plate. Since a large amount of heat is generated, it is inevitable that uneven distribution in the heating temperature is likely to occur, and as a result, good thermal oxidation work cannot be realized, which is a problem.

In view of the above-mentioned circumstances, an object of the present invention is to provide a wafer printing apparatus which can realize a uniform temperature distribution over the entire surface with high accuracy and can obtain a good heating operation. Is.

[0006]

That is, according to the invention described in claim 1, a wafer having a good thermal conductivity is used, which is formed into a disk shape corresponding to the shape of the wafer and is to be baked on the upper surface. The heat-conducting member which is mounted and in which the heat pipes are radially symmetrically provided on the joint surface side to be joined to each other and the heat-generating member provided on the lower surface of the heat-conducting member are provided. Further, the invention according to claim 2 is provided with a heat conducting member provided with a hollow heat conducting portion over the entire inside thereof, and a heat generating member provided on a lower surface of the heat conducting member.

[0007]

According to the invention of claim 1, the heat pipes embedded in the heat conducting member are arranged radially and symmetrically with respect to the heat conducting member, and the heat generated from the heat generating member is the heat. When the heat is conducted to a part of the pipe, the heat conduction effect of this heat pipe causes the heat to immediately propagate to the entire heat conducting member without causing positional unevenness, and the entire heat conducting member is uniformly heated to a substantially constant temperature. To be done.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic sectional view showing a wafer printing apparatus according to this embodiment. The wafer printing apparatus of this embodiment has a pair of upper and lower heat transfer members 2 in which a heat pipe 1 is radially symmetrically embedded and sandwiched between them, and a lower surface of the heat transfer member 2 on the lower side. The heat generating member 3 is fixedly attached.

The heat pipe 1 is one in which the heat is quickly spread to the whole by only partially (partly) heating, and the whole is heated to a substantially constant temperature. In this embodiment, for example, aluminum or the like is used. Made of material. Further, inside the heat pipe 1, as shown in FIG. 3, a large number of metal whiskers called wicks 11 are planted on the inner wall surface. When a part of the heat pipe 1 is heated, the moisture inside becomes steam and quickly flows to the cold (low temperature) part, and the wick 11 in the cold part condenses and adheres with steam, or due to a capillary phenomenon. Water adhering to the inner wall surface of the heat pipe 1 is sucked up between the wicks 11. The heat pipe 1 of this embodiment is, as shown in FIG.
It is composed of L and 1S and arranged alternately.

In this embodiment, the heat conducting member 2 is made of aluminum, which has a good heat conductivity, and is a pair of substantially discs having a diameter corresponding to the size of the wafer to be baked. It is composed of an aluminum plate. In addition, a recess 2 for burying the heat pipe 1 is formed in a part of a joint surface where these heat conducting members 2 are joined to each other.
A is formed.

The heat generating member 3 of this embodiment is the heat conducting member 2
A silicon rubber heater having a thickness of about 1 mm formed in the same size as the above is used, and is electrically energized to generate heat.

The wafer printing apparatus according to the present invention is not particularly limited to this embodiment. For example, as shown in FIG. 4, the entire inner surface of the heat conducting member 2'is formed into a hollow shape. A wick 11 may be provided on the inner wall surface to serve as a heat space instead of the heat pipe. In this case, the surface temperature can be made more uniform than in the case of the previous embodiment.

[0013]

Therefore, according to the invention of claim 1,
The heat pipe embedded in the heat conducting member is arranged radially and symmetrically with respect to the heat conducting member, and when the heat generated from this heat generating member is conducted to a part of the heat pipe, the heat generated by this heat pipe Due to the conduction effect, the heat immediately spreads and propagates to the entire heat conducting member without causing partial unevenness, and the entire heat conducting member is evenly heated to a substantially constant temperature, resulting in a uniform temperature distribution over the entire surface. In addition, it can be realized with high accuracy in a very short time, and as a result, a good heating action for the wafer can be exhibited.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing a wafer printing apparatus according to the present invention.

FIG. 2 is a plan view of the device.

FIG. 3 is a partially enlarged view of the device.

FIG. 4 is a schematic sectional view showing a modified example of the wafer printing apparatus according to the present invention.

FIG. 5 is a schematic cross-sectional view showing a conventional example.

[Explanation of symbols]

 1 heat pipe 2 2'heat conducting member 3 heat generating member 11 wick

Claims (2)

[Claims] 1. A wafer, which is made of a material having good thermal conductivity, is formed into a disc shape matching the shape of a wafer, and a wafer to be baked is mounted on the upper surface of the heat pipe (1). A wafer printing apparatus comprising: a heat conducting member (2) provided radially and symmetrically; and a heat generating member (3) provided on a lower surface of the heat conducting member (2). 2. A heat-conducting member (2 ′) having a hollow heat-conducting portion throughout the inside, and a heat-generating member (3) provided on the lower surface of the heat-conducting member (2 ′).
An apparatus for printing a wafer, comprising: