CN201112360Y - reaction chamber - Google Patents

Abstract

A reaction chamber is suitable for a plasma process machine, wherein the reaction chamber has an opening, and a shield is arranged on the surface of the opening, wherein the shield is opposite to the surface of a wafer, and the surface of the shield is a rough surface. The rough surface of the shield can increase the area of adhesion and coating, reduce the situation of peeling, and thus reduce the pollution of particles.

Description

reaction chamber

technical field

The utility model relates to a semiconductor device, in particular to a reaction chamber used in a plasma etching process.

Background technique

Plasma is a partially ionized gas that is accelerated by an electric field and collides with molecules or atomic groups to generate ionization reactions. In semiconductor technology, plasma (plasma) is widely used, such as cleaning (cleaning), coating (coating), sputtering (sputtering), plasma chemical vapor deposition (plasma CVD), ion implantation (ionimplantation) ) or etching (etching), etc.

Whether it is a plasma cleaning machine, a plasma etching machine or a plasma deposition machine, etc., it will be carried out by ion bombardment (such as bombarding the target or the surface of the wafer), which will cause particles to be generated on the walls of the reaction chamber and the wafer. ,create pollution.

1 and 2 are schematic diagrams illustrating a known flooded plasma system and its reaction chamber and wafer. Taking the ion implantation machine of the submerged plasma flood system (plasma flood system) in Fig. 1 and Fig. 2 as an example, the reaction chamber 100 of the known submerged plasma flood system 105 has an opening 110, and the ray 120 generated in the reaction chamber 100 It is emitted from the opening 110 and hits the wafer 130 . Wherein, the distance between the shutter 140 on the surface of the opening 110 of the reaction chamber 100 and the surface of the wafer 130 is very short, about 10 cm, and the shutter 140 has a smooth surface.

During the ion implantation process, a layer of patterned photoresist is usually formed on the wafer 130 to cover the area where ions are not to be implanted. As the ion implantation proceeds, a large amount of outgas generated in the photoresist adheres to the surface of the opening 110 . When the outgassing is too much, it will cause peeling phenomenon, resulting in the formation of particles, which will contaminate the reaction chamber and the surface of the wafer 130, resulting in a large increase in the number of defects.

Utility model content

In view of this, one of the objectives of the present invention is to provide a reaction chamber with a rough surface to reduce particles caused by ion bombardment, thereby reducing the number of defects and increasing the yield.

The utility model provides a reaction chamber, which is suitable for a plasma process machine. The reaction chamber has an opening, and a shutter is arranged on the surface of the opening, wherein the shutter is opposite to the surface of a wafer, and the surface of the shutter is a rough surface.

According to the reaction chamber described in the embodiment of the present invention, wherein the rough surface includes a wavy surface or a serrated surface.

According to the reaction chamber described in the embodiment of the present invention, the surface of the shutter includes a plurality of horizontal lines or a plurality of straight lines.

According to the reaction chamber described in the embodiment of the present invention, the surface of the shutter includes a plurality of dispersed protrusions.

According to the reaction chamber described in the embodiment of the present invention, the shield includes an upper shield and a lower shield, which are fixed on the surface of the opening.

According to the reaction chamber described in the embodiment of the present invention, the upper shutter and the lower shutter form an angle.

According to the reaction chamber described in the embodiment of the present invention, the upper shutter and the lower shutter are respectively in the shape of a ㄇ.

In the reaction chamber according to the embodiment of the present invention, the material of the shutter includes graphite.

According to the reaction chamber described in the embodiment of the present invention, the material of the reaction chamber includes graphite.

According to the reaction chamber described in the embodiment of the present invention, the reaction chamber is suitable for a flooded plasma system (Plasma Flood System).

In the reaction chamber according to the embodiment of the present invention, the plasma process machine includes a plasma cleaning machine, a plasma etching machine, a plasma deposition machine and a plasma injection machine.

Because the utility model adopts the opening of the reaction chamber with a rough surface, in the step of performing the plasma process, the surface area of the attached coating can be effectively increased to reduce the chance of peeling off, which not only greatly reduces the number of defects, but also improves the processing efficiency. The yield rate also helps to prolong the service life of the shutter and save manufacturing costs.

In order to make the above and other objects, features and advantages of the present invention more comprehensible, preferred embodiments will be described below in detail with reference to the accompanying drawings.

Description of drawings

FIG. 1 is a schematic diagram illustrating the structure of a known flooded plasma system.

FIG. 2 is a schematic diagram illustrating a reaction chamber and a wafer of a conventional flooded plasma system.

FIG. 3A is a structural diagram of a reaction chamber according to an embodiment of the present invention.

FIG. 3B is a view showing a shutter of a reaction chamber according to an embodiment of the present invention.

FIG. 3C is a cross-sectional view of a shutter of a reaction chamber according to an embodiment of the present invention.

FIG. 4 is a graph showing the number of defects of the reaction chamber shutter of the experimental example of the present invention before and after modification.

simple notation

100, 300: reaction chamber

105: Submerged plasma system

110, 310: opening

120: ray

130: chip

140, 340: Shutter

340a: Upper shutter

340b: lower shutter

350: screw

Detailed ways

FIG. 3A is a structural diagram of a reaction chamber according to an embodiment of the present invention. FIG. 3B is a view showing a shutter of a reaction chamber according to an embodiment of the present invention. FIG. 3C is a cross-sectional view of a shutter of a reaction chamber according to an embodiment of the present invention.

In this embodiment, a reaction chamber in a submerged plasma system is taken as an example for illustration. Please refer to FIG. 3A , FIG. 3B and FIG. 3C . The reaction chamber 300 is suitable for a plasma ion implantation machine (not shown).

The material of the reaction chamber 300 is, for example, graphite or aluminum. The rays are emitted through the opening 310 of the reaction chamber 300 and hit the surface of the wafer (not shown). In this embodiment, the submerged plasma system (referring to FIG. 1) is used to perform the doping implantation step on the wafer, and the rays, such as ion beams, will be emitted through the opening 310 and implanted into the wafer (the opposite side of the wafer and the opening of the reaction chamber) The location can be referred to as shown in Figure 2).

A shutter 340 is disposed on the surface of the opening 310 of the reaction chamber 300 . The material of the shutter 340 is, for example, the same as that of the reaction chamber 300, such as aluminum or graphite, preferably graphite. Wherein, the mask 340 is opposite to the surface of the wafer, and the surface of the mask 340 is a rough surface. The rough surface referred to herein may be a wavy surface (as shown in FIG. 3B ), or a jagged surface. The surface of the shroud 340 has, for example, multiple horizontal lines, as shown in FIG. 3A and FIG. 3B . Of course, the surface of the shroud 340 may also have multiple straight lines. In another embodiment, the surface of the shutter can also be provided with a plurality of scattered protrusions to form the rough surface.

Referring to FIGS. 3A and 3B , the shield 340 can be divided into two parts, an upper shield 340 a and a lower shield 340 b. The upper shield 340 a is fixed on the upper half surface of the opening 310 of the reaction chamber 300 , and the lower shield 340 b is fixed on the lower half surface of the opening 310 of the reaction chamber 300 . The upper shield 340 a and the lower shield 340 b are fixed on the reaction chamber 300 by screws 350 , and are closely connected with the reaction chamber 300 (as shown in FIG. 3C ). The two are, for example, matched with the shape of the opening 310 , and are respectively in the shape of a ㄇ, and an angle is formed between the upper shield 340 a and the lower shield 340 b, which is, for example, an obtuse angle greater than 90°.

Since the surface of the shield 340 is rough, the overall coating surface area of the shield 340 can be increased to reduce peeling. This not only reduces the chance of particle generation, helps to keep the reaction chamber 300 and the surface of the wafer clean, but also reduces the number of defects. In addition, the lifetime of the shroud can be extended, thereby reducing the manufacturing cost.

It should be noted that although the above-mentioned embodiment is illustrated by taking the reaction chamber of the submerged plasma system used in the ion implantation process as an example, the present invention is not limited to be used in this system. Other plasma process machines, such as plasma cleaning machines, plasma etching machines, plasma deposition machines and other types of plasma injection machines, can use this kind of reaction chamber proposed by the utility model, and utilize shutters with rough surfaces , to achieve the advantages of reducing the number of defects.

Below just with an experimental example, further illustrate the utility model. FIG. 4 is a graph showing the number of defects of the reaction chamber shutter of the experimental example of the present invention before and after modification.

Please refer to Fig. 4, in this experimental example, be with the 20th week as the boundary, the reaction chamber proposed by the utility model was not used before the 20th week (W20); as for after the 20th week, the utility model proposed reaction chamber. In this experimental example, the opening of the reaction chamber is provided with a corrugated shutter.

It can be seen from Figure 4 that the average number of defects measured before the 20th week (W20) is 223.3; the average number of defects measured after the 20th week (reformed into a wavy shutter) is 42.2. Obviously, the average number of defects dropped by 181.1 after a moderate modification of the shutter of the opening of the reaction chamber. Therefore, the utility model can greatly suppress the occurrence of peeling, reduce the number of defects of the wafer, and improve the yield. Moreover, the service life of the shutter can also be extended, achieving the effect of saving manufacturing costs.

Although the utility model has been disclosed above with preferred embodiments, it is not intended to limit the utility model. Any person skilled in the art may make some changes and modifications without departing from the spirit and scope of the utility model. Therefore, the protection scope of the present utility model shall be defined by the appended claims.

Claims (10)

1. A reaction chamber, which is suitable for a plasma process machine, is characterized in that the reaction chamber has an opening, and the surface of the opening is provided with a shutter, wherein the shutter is opposite to the surface of the wafer, and the surface of the shutter is rough surface. 2. The reaction chamber according to claim 1, wherein the rough surface comprises a wavy surface or a serrated surface. 3. The reaction chamber as claimed in claim 1, wherein the surface of the shield comprises a plurality of horizontal stripes. 4. The reaction chamber as claimed in claim 1, wherein the surface of the shutter comprises a plurality of straight lines. 5. The reaction chamber as claimed in claim 1, wherein the surface of the shield comprises a plurality of dispersed protrusions. 6. The reaction chamber as claimed in claim 1 , wherein the shield comprises an upper shield and a lower shield, fixed on the surface of the opening. 7. The reaction chamber as claimed in claim 6, wherein the upper shutter forms an angle with the lower shutter. 8. The reaction chamber according to claim 6, wherein the upper shutter and the lower shutter are respectively in the shape of a ㄇ. 9. The reaction chamber as claimed in claim 1, wherein the material of the shutter comprises graphite. 10. The reaction chamber as claimed in claim 1, wherein the material of the reaction chamber comprises graphite.

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