JPH04122045A - Clamp device of wafer and lamp method - Google Patents

Abstract

PURPOSE:To make heat transmission conditions fixed by changing a contact pressure between a wafer and a fixing base in accordance with a pressure difference between an atmospheric pressure of an inside of a bellows and that of an outside thereof. CONSTITUTION:A movable board 4 and a clamp ring 2 are connected to both ends of a rod 3 which passes through a fixing base 1 which is provided with a temperature controlling medium flow path 1a. A bellows 5 is interposed between the base 1 and board 4, and the ring 2 brings a wafer 6 into contact with the fixing base 1 by pressure difference between an atmospheric pressure of an inside of the bellows 5 and that of a periphery thereof. When an atmospheric pressure outside the bellows 5 lowers and vacuum degree increases, a contact pressure between the wafer 6 and the base 1 increases, thereby reducing the contact pressure in accordance with lowering of vacuum degree. Therefore, the higher vacuum degree is, the more effectively it compensates for lowering of heat transmission between the wafer 6 and the base 1. It is therefore possible to correct change of heat transmission in accordance with vacuum degree if conditions are adjusted.

Description

[Detailed Description of the Invention] [Summary] Regarding the improvement of a wafer clamping device and clamping method that changes the clamping pressure according to the atmospheric pressure around the wafer, the degree of vacuum at the contact area between the semiconductor wafer and the fixing table changes. The purpose of the present invention is to provide a wafer clamping device and clamping method that makes it possible to keep the heat conduction state constant during this time even in the case of In,
A fixed base having a temperature control medium flow path therein, a rod passing through the fixed base, a movable plate and a clamp ring coupled to both ends of the rod, and both ends of the fixed base and the movable plate, respectively. The movable plate is airtightly fixed and includes a bellows interposed between the fixed base and the movable plate.

[2] Using the wafer clamping device according to claim 1,
The contact pressure between the wafer and the fixing table by the clamp ring is configured to be changed depending on the pressure difference between the air pressure inside the bellows and the air pressure outside the bellows.

[Industrial application field]

The present invention relates to improvements in a wafer clamping device and clamping method that change clamping pressure depending on the atmospheric pressure around the wafer.

If the contact pressure between a wafer in contact with a fixed table whose temperature is regulated and this fixed table is constant, if the degree of vacuum at the contact area between the wafer and the fixed table is different, the heat between them will increase. Changes occur in transmission.

Under the above circumstances, there is a need for a wafer clamping device and clamping method that can maintain constant heat transfer even when the degree of vacuum at the contact area between the wafer and the fixing table is different. .

[Conventional technology]

A conventional wafer clamping device and method will be explained in detail with reference to FIG.

The conventional wafer clamping device, as shown in Figure 2,
A movable plate 14 and a clamp ring 12 are attached to both ends of the rod that passes through the fixed base 11 in which the temperature control medium flow path 11a is provided.
A spring 15 is interposed between the fixed table 11 and the movable plate 14, and the compressive force of the spring 15 causes the clamp ring I2 to clamp the wafer,
For example, the semiconductor wafer 6 is brought into contact with the fixing table 11.

In such a wafer clamping device, the semiconductor wafer 6 is brought into contact with the fixed metalwork 1 by the clamp ring 12 which is biased by the spring 15, so that the contact pressure therebetween is constant.

[Problem to be solved by the invention]

In the conventional wafer clamping device and clamping method described above, the semiconductor wafer and the fixing table are brought into contact with the clamp ring by the compressive stress of the spring, so the contact pressure is always constant and the degree of vacuum at this contact area There is a problem in that when a change occurs, the state of heat transfer fluctuates.

In view of the above-mentioned circumstances, the present invention provides a wafer clamping device and a clamp that make it possible to keep the heat transfer state constant even when the degree of vacuum at the contact area between the semiconductor wafer and the fixing table changes. It is intended to provide a method.

[Means to solve the problem]

A wafer clamp device of the present invention clamps a wafer using a clamp ring on a fixing base, and includes: a fixing base having a temperature regulating medium flow path inside, a rod passing through the fixing base, and the rod. a movable plate and a clamp ring connected to both ends of the
Both ends of the fixed base and the movable plate are hermetically fixed, respectively, and a bellows is interposed between the fixed base and the movable plate.

The wafer clamping method of the present invention uses the above-mentioned wafer clamping device, and depending on the pressure difference between the internal pressure of the bellows and the pressure outside the bellows,
The clamp ring is configured to change the contact pressure between the wafer and the fixing table.

[Effect]

That is, in the clamp device of the present invention, a flow path for flowing a temperature regulating medium is provided inside the fixed base, and the rod passes through the fixed base, which is maintained at a constant temperature by this temperature regulation.

A movable plate and a clamp ring are connected to both ends of the loft, and both ends of the bellows 5 are fixed to the movable plate and the fixed base.

The wafer held between the clamp ring and the fixing table is kept warm by the fixing table, but if the degree of vacuum at the contact area between the wafer and the delimiting table is different, the pressure difference between the inside and outside of the bellows will cause Since the pressure applied to the wafer by the clamp ring changes, it becomes possible to adjust the contact pressure in accordance with the degree of vacuum at the contact area between the wafer and the fixing table.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS A semiconductor wafer clamping device according to an embodiment of the present invention will be described in detail below with reference to FIG.

As shown in FIG. 1, in the wafer clamping device of this embodiment, a movable plate 4 and a clamp ring 2 are connected to both ends of a loft 3 that passes through a fixed table 1 in which a temperature control medium flow path 1a is provided. A bellows 5 is interposed between the fixed base 1 and the movable plate 4, and the difference between the air pressure inside the bellows 5 and the surrounding air pressure causes the clamp ring 2 to
A wafer, for example a semiconductor wafer 6, is brought into contact with the fixing table 1.

In the wafer clamping device of this embodiment, both ends of the bellows 5 are soldered to the fixed table 1 and the movable plate 4 so as to be airtight, so the amount of gas, for example, air, sealed inside the bellows 5 is reduced. is held constant.

Therefore, the semiconductor wafer 6 applied to the clamp ring 2 by the bellows 5 via the movable plate 4 and the rod 3 depends on the change in the pressure of the air outside the bellows 5, such as at the contact area between the semiconductor wafer 6 and the fixed base l. The contact state with the fixed base 1 changes.

That is, as the pressure of the air outside the bellows 5 decreases and the degree of vacuum increases, the contact pressure between the semiconductor wafer 6 and the fixing table 1 increases, and as the degree of vacuum decreases, this contact pressure decreases.

This has the effect of compensating for the fact that the higher the degree of vacuum, the worse the heat transfer between the semiconductor wafer 6 and the fixing table 1. By adjusting the conditions, it is possible to compensate for variations in heat transfer due to the degree of vacuum. becomes.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, by extremely simple structural changes, it is possible to change the contact state between the heating body and the heated object according to the change in the degree of vacuum in a vacuum. It is possible to provide a wafer clamping device and a clamping method that have advantages such as being able to stabilize the heat transfer state and can be expected to have significant economic and reliability improvement effects.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a semiconductor wafer clamping device according to an embodiment of the present invention, and FIG. 2 is a diagram showing a conventional semiconductor wafer clamping device. In the figure, 1 is a fixed base, la is a temperature control medium flow path, 2 is a clamp ring, 3 is a rod, 4 is a movable plate, 5 is a bellows, and 6 is a semiconductor wafer.

Claims (1)

[Scope of Claims] [1] A clamp device for clamping a wafer (6) on a fixing table (1) using a clamp ring (2), which comprises a fixing table (1) having a temperature regulating medium flow path (1a) inside. 1), a rod (3) passing through the fixed base (1), a movable plate (4) and a clamp ring (2) coupled to both ends of the rod (3), and the fixed base (1). and the movable plate (4), both ends of which are airtightly fixed to the fixed base (1) and the movable plate (4).
4) A wafer clamping device characterized in that it has a bellows (5) interposed between the wafer clamping device and the bellows (5). [2] Using the wafer clamping device according to claim 1,
The clamp ring (2) is adjusted depending on the pressure difference between the air pressure inside the bellows (5) and the air pressure outside the bellows (5).
A method for clamping a wafer, characterized in that the contact pressure between the wafer (6) and the fixing table (1) is changed.