CN103861844A

CN103861844A - Method for cleaning chamber of PAD etching machine

Info

Publication number: CN103861844A
Application number: CN201210550557.3A
Authority: CN
Inventors: 陆连; 张旭
Original assignee: Shanghai Huahong Grace Semiconductor Manufacturing Corp
Current assignee: Shanghai Huahong Grace Semiconductor Manufacturing Corp
Priority date: 2012-12-18
Filing date: 2012-12-18
Publication date: 2014-06-18

Abstract

The invention discloses a method for cleaning a chamber of a PAD etching machine. According to the method, plasma of CF4 gas and metal ingredient-contained polymers gathered in the middle of a top electrode of the etching machine react, and therefore, the goal that the chamber of the PAD etching machine is cleaned is achieved, so the stability of PAD etching rate and etching uniformity are guaranteed, and the MTBC (maintenance times of periodic cleaning) and the normal operation time of the etched process chamber are increased.

Description

The clean method of PAD etching machine bench process cavity

Technical field

The present invention relates to integrated circuit and manufacture field, particularly relate to the clean method of PAD etching machine bench process cavity.

Background technology

In semiconductor fabrication process, PAD(pad) etching technics can produce more product, and particularly for aperture opening ratio product bigger than normal, can produce the polymer of a large amount of containing metal compositions, and be gathered in the middle of upper electrode, as shown in Figure 2.This can cause the etching machine bench speed OOS(ultra-specification abnormal), cannot normal operation, need to clean chamber(process cavity) after just can resume operation, this MTBC(that makes process cavity periodically cleaning safeguards frequency) greatly shorten, the uptime also greatly reduces.

Summary of the invention

The technical problem to be solved in the present invention is to provide a kind of clean method of PAD etching machine bench process cavity, and it can ensure the stability of PAD etch rate.

For solving the problems of the technologies described above, the clean method of PAD etching machine bench process cavity of the present invention, is to use CF ₄the plasma of gas reacts with the polymer of the containing metal composition that is gathered in etching machine bench upper electrode centre.

The present invention utilizes CF ₄the plasma of γ-ray emission is removed the polymer in the middle of PAD etching machine bench upper electrode, reach the object of clean PAD etching machine bench process cavity, the stability of PAD etch rate and the homogeneity of etching are guaranteed, thereby have increased MTBC and the uptime in etching technics chamber.

Brief description of the drawings

Fig. 1 is that process cavity is at the normal condition schematic diagram carrying out before the operation of PAD etching.

Fig. 2 is that process cavity is being carried out the post-job abnormality schematic diagram of PAD etching.

Fig. 3 is the clean method schematic flow sheet of the PAD etching machine bench process cavity of the embodiment of the present invention.

Fig. 4 is the forward and backward PAD etch rate of the clean method of the application embodiment of the present invention and the comparison diagram of etching homogeneity.

In figure, description of reference numerals is as follows:

1: process cavity

2: upper electrode

3: polymer

4: silicon mating plate

Detailed description of the invention

Understand for technology contents of the present invention, feature and effect being had more specifically, existing in conjunction with illustrated embodiment, details are as follows:

The present invention utilizes CF ₄the plasma of gas is removed the polymer of the containing metal composition in the middle of PAD etching machine bench upper electrode, and concrete grammar is as follows;

Step 1, etching technics chamber 1 is carrying out before the operation of PAD etching, and upper electrode 2 surface clean, do not have polymer to adhere to, and as shown in Figure 1, at this moment PAD etch rate is normal.When etching machine bench completes in batches PAD etching operation, upper electrode 2 is assembled (see figure 2) after the polymer of more containing metal composition, and etch rate obviously accelerates, and homogeneity variation, as shown in Figure 4, now, a slice silicon mating plate 4 is sent in etching cavity, then passes into the CF of 20～100SCCM ₄gas, under certain low pressure (5～25Pa) condition, and under radio-frequency power (500～1500W) effect, produces CF plasma.CF plasma and polymer 3 react, and polymer 3 is removed, and process cavity 1 are played to season(preheating machine simultaneously) effect.

Step 2, polymer 3 remove clean after, to the N that passes into 20～50SCCM in process cavity 1 ₂, developing technique chamber 1, reduces the interior particle that may exist of process cavity 1.

After above-mentioned cleaning, etching technics chamber returns to normal condition, PAD etch rate be improved significantly, as shown in Figure 4, the fluctuation of etch rate obviously diminishes, the stability of etch rate and the homogeneity of etching all obtain raising, have so just increased MTBC and the uptime in etching technics chamber.

Claims

The clean method of 1.PAD etching machine bench process cavity, is characterized in that, uses CF ₄the plasma of gas reacts with the polymer of the containing metal composition that is gathered in etching machine bench upper electrode centre.
2. method according to claim 1, is characterized in that, step comprises: silicon mating plate is sent in process cavity, then passes into CF ₄gas, adds radio-frequency voltage, produces CF plasma, reacts with polymer, and polymer is removed.
3. method according to claim 2, is characterized in that, described CF ₄the amount of gas is 20～100SCCM.
4. method according to claim 2, is characterized in that, described radio-frequency power is 500～1500W.
5. method according to claim 2, is characterized in that, the pressure in process cavity is 5～25Pa.
6. the method described in any one according to claim 2 to 5, is characterized in that, also comprises step: polymer remove clean after, use nitrogen wash process cavity, the particle in removing process cavity.
7. method according to claim 6, is characterized in that, the amount of described nitrogen is 20～50SCCM.