JPS61281527A - Semiconductor wafer heat-processing device - Google Patents

Abstract

PURPOSE:To improve the yield ratio of wafers by constructing the device having a minimum chamber as necessary on the both or one side of the upper plate and lower plate. CONSTITUTION:A plane-shaped heating plate 9 whose heater pattern 90 is altered is used under the consideration of the heat inclination from the middle part to the end part of the upper plate 1 on the surface 1, and the chamber's cubic volume of the upper plate and a lower plate 2 is made minimum as necessary. After a wafer is transported on the plate surface whose temperature is made uniform, vacuum sucking is performed using a sucking and pressurizing hose for suction release 4 of the lower plate 2 through the first and second chambers for sucking 8, 80 and via a sucking hole 7b for the upper plate 1 so as to forcibly suck the wafer on the surface of the processing plate, thereby improving the yield ratio of the throughput to production.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a semiconductor wafer heat treatment apparatus used in semiconductor manufacturing.

[Conventional technology]

Semiconductor devices such as ICs, ) transistors, and thyristors are 1.
It is formed by repeatedly subjecting a silicon wafer to processes such as diffusion and photolithography. In the photolithography process, a resist is coated on the wafer in order to transfer and draw the necessary pattern, and is forcefully dried and fixed. The semiconductor wafer heat treatment apparatus of the present invention is used to forcefully dry and fix the resist coated on the wafer.

The general structure of the conventional device is shown in FIG. 9, and mainly includes a -L plate 1 on which the evaporators are placed and heated after being adsorbed, and a lower plate 2 having cylindrical horseshoe-shaped heating elements 3a, 3b, etc. I can't understand the composition. " ・ " □ To explain this conventional semiconductor wafer heat processing apparatus in more detail, as shown in FIG. 9 and FIG. A -L plate 1 having a suction hole 7b used for suction release pressurization and on which a wafer is placed for suction and heating, cylindrical horseshoe-shaped heating elements 3a, 3b, metal fittings for suction and suction release pressurization, and a hose 4. , a lower plate 2 having a thermocouple 5 used to measure and maintain the surface temperature of the processing plate, and a suction chamber 8 which is a cylindrical hole for making the wafer suction force uniform over the entire surface; It is in the structure.

A conventional semiconductor wafer heat treatment plate is constructed as described above, and after the wafer is coated with resist in the pretreatment unit, the lower plate 2 is coated in advance as shown in FIGS. 9 and 10.
A state in which the processing plate surface 1 is heated through the air layer of the adsorption chamber 8, which takes into account the thermal gradient from the center to the edge of the surface of the processing plate surface 1, and the temperature variation on the processing plate surface is large. is conveyed to the plate surface of the upper plate 1. Then, a vacuum is drawn through the suction and suction release of the lower plate 2 through the pressurizing fitting and hose 4, the suction chamber 8, and the suction hole 7b of the upper plate 1, and the wafer is forcibly adsorbed onto the heated processing plate. The resist is forcibly dried and fixed on the wafer.

[Problem that the invention seeks to solve]

As shown in FIGS. 9 and 10, the conventional semiconductor wafer heat processing plate described above requires the wafer to be uniformly attracted to the entire surface through the processing plate upper plate 1 and heated uniformly. The structure for heating inside the plate 2 is a cylindrical horse M
Since it is composed of two heating elements 3a and 3b and generates a certain amount of heat in a limited area, a temperature gradient occurs on the surface of the processing plate, and at the same time, because the lower plate 2 has a chamber 8. Furthermore, it has a structure that creates a temperature gradient.

This resulted in a drawback that the manufacturing yield of wafers decreased. −° ・−゛This invention was made in order to eliminate the above-mentioned conventional drawbacks.゛It is possible to obtain a semiconductor wafer heat processing apparatus that does not generate a temperature gradient on the surface of the processing plate and has a good wafer production yield. The purpose is to.゛ [Means to solve the problem] ゛ ・
- The semiconductor wafer heat treatment apparatus according to the present invention uses a planar heating element that changes the amount of heat generated at each location in consideration of the temperature gradient on the surface of the processing plate to make the temperature uniform on the surface within the plane, In order to achieve uniform adsorption and adsorption release pressure over the entire surface, it has a black square structure with a minimum number of chambers on both or one of the upper plate side and the lower plate side.
[Operation] In this invention, the surface of the processing plate is made to have a uniform temperature distribution by taking into account the heat f-slope of the heat distribution from the center to the ends of the heat processing plate. We have changed the heat generation valve device for each place where it is movable, and adopted a planar waste heat body that is weighted with a weight of □. In order to provide a chamber function on the upper plate side within a range that is not affected by temperature variations, we have installed the minimum necessary chambers near all the suction holes on the north side and on the lower side of the upper plate, which reduces heat significantly compared to conventional structures. This creates a uniform conductivity, eliminates temperature variations on the surface of the processing plate, and ``Since the entire surface is evenly adsorbed, variations within a wafer and between wafers are eliminated, improving throughput and improving wafer manufacturing yield. You can improve.

〔Example〕

FIG. 2 is a sectional view of the processing plate of the above embodiment, and FIG. 3 is a bottom view and a sectional view of the upper plate of the processing plate.

In these figures, the same reference numerals as those in FIGS. 9 to 11 above indicate corresponding parts.

In the figure, 9 is a plate 1 arranged over the entire area of the lower plate 2.
0 is a ring or gasket for preventing the leakage of suction force and suction release pressure when joining the upper plate I and the lower plate 2, and 11 is a heat-resistant material for protecting the planar heating plate 9 and preventing dust generation. A dust generation corrosion resistant plate, 5 a thermocouple for maintaining and managing the temperature on the surface of the processing plate, 4 metal fittings and hoses for transmitting adsorption force and adsorption release pressure, 12 a planar heating plate 9 of the lower plate 2 and heat resistant Dust generation prevention 1 ring to prevent dust generation from the central joint with the dust-free corrosion-resistant Fi11, 8 is a lower plate 2 and a planar heating plate 9 to uniformly adsorb the wafer over the entire surface, heat-resistant dust-free This is a cylindrical first adsorption chamber of the minimum necessary size that is formed when the corrosion-resistant plate 11 and the dust prevention ring 12 are combined, and the lower plate 2 is composed of these members.

Further, 7b is a suction hole for transmitting suction and suction release pressure to the wafer, and 80 is a suction hole of the minimum necessary size within a range that does not reduce thermal conductivity, and is capable of uniformly suctioning the wafer over the entire surface.
A second adsorption chamber in which the vicinity of the adsorption holes 7b on the bottom side of the second plate L of the processing plate are all connected by a thin and shallow groove; 6 is a temperature fuse for controlling the surface temperature to prevent runaway; The upper plate 1 is constructed from the above.

In addition, Figure 8 is for the main processing plate, taking into account the temperature gradient,
A planar heat generating plate 9 is shown in which there are more heat generating lids at the ends than at the center. Although the heat generating element pattern 90 of the planar heat generating plate 9 has a hook shape in this embodiment, it may have various other shapes such as a spiral shape and a circular shape.

Next, we will discuss the effects.

In such an embodiment, the heating element pattern 90 is designed in consideration of the thermal gradient from the center to the end of the plate top plate 1.
Using a planar heating plate 9 with different
Since the volume of the chang is minimized to the necessary minimum to improve thermal conductivity, there is no fluctuation in the plate surface temperature of the upper plate 1 and a uniform temperature state is achieved. Therefore, after the wafer is transferred to the plate surface which has been brought into a uniform temperature state, the lower plate 2 is adsorbed and the adsorption release pressurizing hose 4. 1st. The wafer is heated uniformly by passing through the second suction chamber 8° 80 and through the suction hole 7b of the upper plate 1 and forcibly adsorbing the wafer to the surface of the processing plate. can be force-dried and fixed to the wafer.

In the first embodiment, the processing plate has a cylindrical first adsorption chamber 8 between the upper plate 1 and the lower plate 2, but the processing plate does not have this. It's okay.

Moreover, FIGS. 4 and 5 are diagrams for explaining a second embodiment of the present invention. In this embodiment, a planar heat generating plate 9 is used as a heat source and the adsorption capacity is maintained. At the same time, in order to bring the heating element closer to the upper plate L side, the second adsorption chamber 80 on the upper plate 1 side has a structure in which the bottom cross section is inclined in the radial direction at 1 so that the height is higher at the center.・I'm exhausted. Therefore, in this embodiment, in addition to the effects described in Section 1-E, the semiconductor wafer can be heated more uniformly and the heating time can be shortened.

Further, FIGS. 6 and 7 are diagrams for explaining a third embodiment, and in this embodiment, the second adsorption chamber 80 on the upper plate L side is lowered at the center of its bottom cross section. In this case, the same effect as in the second embodiment is achieved.

In addition, in the first to third embodiments, the heat generation amount of each part of the heating element pattern 90 of the planar heating plate 9 was set in consideration of the temperature gradient of the processing plate. The heating element patterns 9 and 0 may be configured such that the outer portion generates a larger amount of heat than the inner portion, resulting in an even greater effect. [Effects of the Invention] As described above, according to the present invention, in a semiconductor wafer heat treatment plate, - a planar heating element structure capable of making the upper plate surface temperature uniform; In order to reduce the air space between the lower plate and improve the heat transfer coefficient, the lower plate's adsorption chamber is made shallower, and the upper plate's adsorption chamber is shallower.
The structure has shallow, thin, and long grooves on the top plate side that connect only the surrounding areas, so that uniform adsorption and uniform heating are possible, and the thickness of the sea urchin pigeon film is uniform, and the heating time is also shortened. Effects such as improved throughput and improved manufacturing yield can be obtained at the same time.

[Brief explanation of drawings]

Figure 1 is the first example of the present invention! 2 is a detailed longitudinal sectional view of the processing plate 1 according to the embodiment, FIG. 3 is a bottom view and sectional view of the processing plate 114, and the 41st recess is a main FIG. 5 is a longitudinal cross-sectional view of a processing plate according to a second embodiment of the invention; FIG. 5 is a bottom view and cross-sectional view of the upper plate;
The figure is a longitudinal sectional view of a processing plate according to a third embodiment of the present invention.
FIG. 7 is a bottom view and a sectional view of the plate, FIG. 8 is a plan view of the planar heating plate of each embodiment, and FIG. 9 is a schematic structure and longitudinal sectional view of a conventional treatment plate. FIG. 10 is a detailed vertical cross-sectional view of the processing plate 1, and FIG. 1I is a top view and cross-sectional view of the upper plate of Mit. l...Top plate, 2...F plate, 4...Hose for adsorption and removal of adsorption, 5...Thermocouple, 6...Temperature fuse,
7b... Adsorption f on the hand plate, 8... First adsorption chamber, 8a, 8b... Inclined box, 9... Planar heating plate, 80... Second adsorption chamber, 90... Heating element pattern. In the middle of the figure, the reference numbers indicate the same or corresponding parts. Figure 9 (C)

Claims (5)

[Claims] (1) A semiconductor wafer heat treatment apparatus having a plate for heat treating a semiconductor wafer, characterized in that the treatment plate has a planar heating element therein for heating the treatment plate so that its surface temperature is uniform. Semiconductor wafer heat treatment equipment. (2) The semiconductor wafer heat processing apparatus according to claim 1, wherein the upper plate is formed with a wafer suction groove that makes the wafer suction force uniform on the surface of the processing plate. (3) The semiconductor wafer heat processing apparatus according to claim 2, wherein the processing plate has a thin air layer between the upper plate and the lower plate. (4) The semiconductor wafer heat processing apparatus according to claim 2 or 3, wherein the wafer suction groove of the upper plate has a bottom cross section inclined in the radial direction. (5) The heating element pattern of the planar heating element is a heating element pattern in which the amount of heat generated in the outer part is larger than that in the inner part. Semiconductor wafer heat treatment equipment.