JPS60223125A - Dry-process device - Google Patents

Abstract

PURPOSE:To release wafer-chucking without shocking a wafer by providing a mechanism vertically moving a member fixing and holding an elastic supporter. CONSTITUTION:A wafer hold-down 19 is fitted to an electrode holder 15 and a connecting rod 31 penetrating an insulator 26, and moved vertically as shown in the figure by a drive 32 such as a solenoid. O rings 33 are mounted to the electrode holder 15, and a seal L and the inside of a chamber 17 are kept vacuum. When etching is completed and the connecting rod 31 is pushed up, a wafer hold- down surface 30 is detached from a wafer 5 because the outer circumferential section of the wafer 5 is pressed down by the resilient force of a plurality of elastic supporters 29 for the wafer hold-down 19. When the wafer hold-down surface 30 is further moved upward, the elastic supporters 29 are separated while pushing down the wafer 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a method for dry processing of materials by dry processing using a plasma spike or a reactive spa bath and processing device. Related to process equipment.

[Background of the invention]

As semiconductor devices become more sophisticated and highly integrated.

Technology for forming fine patterns has become extremely important. In conventional wet etching methods that utilize chemical reactions, the etching progresses isotropically, resulting in under-pressure, making it difficult to accurately transfer fine patterns. In this dry etching method, the etched material is in the form of scum, and the scum particles are ionized and bombarded onto the sample to be edited. The chemical eroding effect of radicals that occur during this process can be counteracted by the physical removal of ions or by the synergistic effect of the two.

FIG. 1 is a cross-sectional view of the structure of a dry etching apparatus manufactured by Jubei.

For example, a dry etching method will be described in which one wiring pattern is formed on the object to be etched.

Transfer carbon tetrachloride (ccn,) scum from gas source 1 to valve 1A
is introduced into the etching chamber 2, which is evacuated through the valve V by a one-turn pump R, P0. The pressure inside the etching chamber is valve 1A.
The pressure is adjusted to around 0.1 Torr using A high frequency power source 3 of 13.56 MHz is applied to the electrode 4 provided in this checkbox 2fE3&n.

A high frequency power of about 100 to 200 W is applied.

Then, ions P such as CCII, - ions and chloride ions and chlorine radicals are generated, and these ions are transferred to the object to be etched (hereinafter referred to as wafer in this specification) 5 placed on the electrode 4. collide, and AI! , the membrane is etched.

At this time, in the case of reactive ion/etching, the etchant, socin, scum, and reaction products cause an M combination reaction in the plasma.
A polymer film 6 is attached to the wafer 5 and the wafer presser 7.

Conventionally, in order to speed up dry machining, it is necessary to increase the voltage applied to the electrodes. Therefore, the high-frequency power must be increased.1 For example, the temperature of the wafer rises significantly due to electrons, ions, radiation, etc. generated by plasma discharge, and normal etching cannot be performed due to sagging or deterioration of the photosensitive resin mask. There was a problem.

Accordingly, it becomes necessary to cool the wafer.

The simplest cooling method is to place cooling water 8 inside the electrode 4.
The heat of the wafer is released to the electrode side by cooling the electrode by flowing water (Figure 2). In order to cool the electrode more efficiently, it is preferable to bring the wetted material 5 into close contact with the electrode surface 9 to maintain thermal contact.

For this purpose, the surface of the electrode 4 is formed into a convex shape, and in order to bring the wafer 5 into strong contact with the convexity (N), the external part of the wafer is pressed down.

It has been reported, for example, in Japanese Patent Application Laid-open No. 40781/1983 entitled "Dry Etching Method" filed by the present applicant. Another way to increase the cooling effect is to introduce a gas such as Ar between the wafer 5 and the electrode 4, which increases the amount of heat transferred from the wafer 5 to the electrode 4, thereby increasing the cooling effect. Japanese Patent Application Publication No. 4M-10 filed by Bali 77
It is reported in No. 5442.

By cooling the wafer as described above, it is possible to speed up the dry etching process, but the adhesion of the polymer 6 to the wafer surface caused by the etching described above poses a problem. It is a member 1o that presses down the external part of the wafer during wafer cooling.
When the polymer film 6 extends over the area, this film acts as an adhesive, and the wafer 5 cannot be removed from the wafer holding member 10.
It was a problem. In production dry etching equipment, wafers are automatically transported, but in this case, wafer transport becomes defective, resulting in a large problem with stable operation of the equipment.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a dry process apparatus that makes it possible to easily separate a wafer from a wafer holding part.

[Summary of the invention]

In order to achieve the above object, the dry process apparatus according to the present invention includes an etched object which is placed on an electrode to which high frequency power is applied and whose outer periphery is pressed by a plurality of elastic supports. The gist of the present invention is to include a holding part, an object holding surface for holding down the object to be etched in a region other than the area of the holding part, and a mechanism for vertically moving a member for fixing and holding the elastic support. In an advantageous embodiment of the invention, the elastic support is housed inside the object holding part. In a further advantageous embodiment of the invention, a heating device is provided for heating the elastic support.

The present invention will be described in detail below using examples with reference to one drawing, but these are merely illustrative and it is understood that various modifications and improvements may be made without going beyond the scope of the present invention. Of course.

[Embodiments of the invention]

Fig. 3 IAIP and (Bl are cross-sectional views showing a wafer separation state using the wafer holding machine according to the present invention, and Fig. 4 is a partially block diagram showing a mechanism for attaching and detaching the object to be etched according to the present invention. FIG. 5 is a cross-sectional view of a dry machining device using the same method, and FIG. 5 is a plan view of the device shown in FIG.

The electrode holder 15 is freely opened and closed and comes into contact with the chamber 17 via the QI/ring 16 to form an ebbing N. Then, the working gas is introduced through the gas introduction pipe 17a and released through the exhaust pipe 17b, as shown in the figure.

While the chamber 17 is grounded, the counter electrode &18 is folded inwardly, and a wafer holder 19 made of a quartz plate is arranged to hold the outer periphery of the wafer 5 placed on the wafer mounting surface 2°A which forms the upper surface of the electrode 2a. Configure it so that it can be pressed down. Mani, electric & is 0
It has a lower electrode 22 and a wafer mounting surface 2OA that come into contact with each other through a ring 21, and has a built-in drain pipe 23, and cooling water circulates inside the electrode 20 as shown by the arrow and is drained from the drain pipe 23. At the same time, the pressure control valve 24 and the water temperature control 25 adjust the water pressure and water temperature of the cooling water flowing into the electrode through the cooling water flow path. Next, the electrode and the electrode holder 15 are insulated by interposing an insulator 26, and both are sealed by a θ ring 27 and
A high frequency power source 28 is connected to the first part 22, and the electrode holder 15 is formed to move up and down in the direction of the arrow in the figure.

First, the electrode holder 15 is lowered, and the wafer 5 is placed on the wafer mounting surface 20A away from the chamber. Next, the electrode holder is raised, and the outer periphery of the wafer 5 is fixed in the electrode holder 20 by the plurality of elastic supports 29 arranged inside the wafer holder 19 and the wafer contact surface adjacent to the elastic supports. When the pressure of the cooling water is adjusted to expand the wafer mounting surface 20A into a convex shape, the entire surface of the wafer 5 is brought into close contact with the wafer mounting surface 20A, and cooling is performed.

Next, a wafer holding mechanism according to the present invention will be described.

The wafer holder 19 is fitted into a connecting rod 31 that connects the electrode holder 15 and the insulator 26, and connects the wafer holder 19 with a drive device such as a solenoid.
L32 moves it up and down as shown. An O-ring 33 is provided on the electrode holder to keep the seal L and chamber 17 in a vacuum. After finishing the engineering and I-ching, connect the connecting rod 31
When the wafer is pushed upward, first, since the outer circumference of the wafer 5 is pressed by the spring blades of the plurality of elastic supports 29 of the wafer presser 19, the wafer presser surface 3o is separated from the wafer 5 (No. 3-81). o After this, the wafer holding surface 30
When the elastic support 29 moves roughly upward, the wafer 5
Separate by pressing down. The elastic support 29 used in the present invention is a plate spring made of stainless steel, and as shown in the sixth column, a coil spring 35 and a pressing pin 36 are built into the plurality of holes 57Vc of the wafer holding part 19. This method may also be used.

A second feature of the present invention is that the elastic support 29 is
The elastic support 29 is housed inside the elastic support 29.
Since the stainless steel leaf springs are not exposed to plasma, there is no heavy metal contamination of the device being engineered.

For reference, FIG. 7 is a cross-sectional view of a wafer holding mechanism that does not have this feature. In this structure, the elastic support 29 does not come out at 1 p.m., and the plasma is exposed to the wafer, which is not preferable. 2. 1 elastic support 29 as shown in Figure 3 IAI
The height dimension X for accommodating the small foil 1 is larger than the sheath width of the plasma so that the elastic support 1 is not exposed to the plasma. Although this height dimension varies depending on the high frequency power, gas pressure, etc., it is sufficient that it is about 2 heads.

A small amount of polymer adheres to the elastic support 29, and when the elastic support is separated, the wafer may not be separated from the elastic support, although this may occur very occasionally. According to the third feature of the present invention, applying heat from the outside to soften the polymer,
This evaporation facilitates wafer transfer. As shown in FIG. 4, the heater wire 40, which is sealed inside the connecting rod 31, passes through the presser foot 19 and is connected and fixed to the elastic support 29. Linking@
The heater wire 40 extending from 51 is connected to an external heater power source 41.
The heating device for the elastic support body 29 is configured to be directly connected to the elastic support body 29. Figure 3! When the heating device for the elastic support 29 is used, the temperature of the elastic support 29 increases and the polymer 1 softens and evaporates.

In addition to the wafers already mentioned, this invention can be applied to photomasks and Class 11, and in addition to dry processing equipment, it can also be used in sputtering equipment, CVD equipment, wafer cooling equipment after pagering, etc. Of course.

〔Effect of the invention〕

As explained above, according to the present invention, wet chucking can be removed without impacting the wafer, which reduces damage to the wafer and contributes to improved quality. Furthermore, since the wafer can be held and removed reliably, the amount of work can be increased.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of the structure of a conventional dry etching/etching device, and Fig. 2 is a cross-sectional view of the chipping mechanism for an object to be etched in a conventional dry etching device.
h and IB+ are cross-sectional views showing the wafer separation state using the wafer holding mechanism according to the present invention, and FIG. 4 is a partial flow diagram. FIG. 5 is a plan view of the device shown in FIG. 4, and FIG. 6 is a sectional view of another dry etching device according to the present invention. A cross-sectional view of the mechanism, FIG. 7, is shown for reference. FIG. 4 is a cross-sectional view of a wafer holding mechanism corresponding to FIG. 3 without the features of the X invention; 19... Wafer holder, 29... Elastic support, 3o.
...Wafer holding surface, 31...Connecting rod, 4o...Heater wire, 41...Heater power supply. ;t'1 Fig. 2 (A) (e) Fang 4 Fig. 17 +5 Fig. 1L/ Fang 6 Fig.

Claims (3)

[Claims] (1) Plasma Nuba 9 or Reactive Nuba 9
In a dry process device that processes materials by dry-neeling using an etching device, a plurality of etching devices are placed on an electrode to which high-frequency power is applied. A work piece/giveter holding part that presses the work piece with two elastic supports, a workpiece holding surface that presses the work piece to be etched in areas other than the area of the holding part, and a member that fixes and holds the elastic support body in the vertical direction. A dry process device characterized by comprising: a mechanism for making S work. (2) The dry processing apparatus according to claim 1, wherein the elastic support is housed inside a workpiece holding part. (3) The dry process apparatus according to claim 1, further comprising a heating device for heating the elastic support.