JPS605528A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To prevent the corrosion of an Al wiring after an wafer was drawn out in the air by a method wherein the wafer formed with the aluminum wiring body according to a dry etching, wherein reaction gas of the chlorine system is used, is heated to specific temperatures, and after that, the wafer is washed with water. CONSTITUTION:A wafer formed with an aluminum wiring body according to a dry etching, wherein reaction gas of the chlorine system is used, is heated to temperatures of not less than 100 deg.C and not more than 200 deg.C, and after that, the wafer is washed with water. For example, a wafer 11 which ended the dry etching is held for one 1min-5min in a furnace, whose interior has been filled up with N2 gas and has been kept at 180 deg.C, as the wafer 11 has been put in the furnace, and following that, the wafer 11 is washed with pure water for about one minute using an ordianry spinner 12. The time to heat the wafer 11 in the furnace is continued for a period of time of exceeding a little 1min, because the heating time is somewhat short in one minute. Following that, a resist removed by an ordinary ashing technique in the following process and processes such as the formation of an insulating film, etc., are performed. As a result, the amount of chlorine remaining in the wafer is significantly reduced, thereby enabling to upgrade the yield of products and the reliability thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a method for manufacturing a semiconductor device, and more particularly, to a method for manufacturing a semiconductor device, and more specifically, a method for manufacturing a semiconductor device.
The present invention relates to a method for preventing corrosion of wiring bodies.

(2) Background of the Technology In response to the trend toward increasing the degree of integration of semiconductor devices, dry etching is used to form thin interconnects with a width of about 2 μm. An example of this will be explained with reference to the cross-sectional view of FIG. 1. For example, if Δβ
The film is lengthened by evaporation, for example, and the length is patterned to form the β wiring body 2. for that purpose,
A resist film is formed on the β film by, for example, a spin code method (rotary coating method), and this resist M) 4 is subjected to processing (patterning) such as exposure and development to form a resist film 3. Use a mask with chlorine-based reactive gases (e.g. carbon tetrachloride (tJ!), boron trichloride (Bcz3))
The B wiring body 2 having the width described above is formed by etching the At crotch by plasma etching using gases such as etching gases.

(3) Prior art and problems A7? When the wafer is taken out into the atmosphere after the try-etching, chlorine remaining on the side of the etched film body 3 and in the resist causes "FIJ erosion", which causes the so-called worm-eaten phenomenon. When aluminum hydroxide chloride is exposed to moisture in the air, it hydrolyzes and becomes hydrochloric acid, corroding as shown by the diagonal lines in Figure 1. Due to this worm attack, A
The β wiring body designed to have a width of 2 μm becomes about half the width (1 μm), resulting in a high resistance one.

As a measure to prevent the above-mentioned AN from being eaten by insects, it may be necessary to perform post-treatment such as carbon tetrafluoride (Ch 2 ) plasma or oxygen (02) plasma in a vacuum after etching, to thoroughly remove the resist, and then expose the wafer to the atmosphere. be done.

However, in the post-processing using CFl,l, there is a problem that not only the resist but also the underlying ll5G IJ is etched, and in the post-processing using CFl, 02, an An203 film is formed on the ferrite wiring body, and in the post-process. During resist ashing, the resist may not be completely removed. Alternatively, post-treatment by hitting with argon (^r) hardens the resist and makes it difficult to remove. In addition, both of the above methods have the problem of taking too much time.

(4) Purpose of the Invention The present invention solves the above-mentioned conventional problem, and aims at forming an i-wiring body by tri-etching an Aβ film grown on a wafer. An object of the present invention is to provide a method for manufacturing a semiconductor device that prevents corrosion.

(5) Structure and object of the invention According to the present invention, a wafer on which an aluminum wiring body is formed by tri-etching using a chlorine-based reactive gas is heated to a temperature of 100°C or more and less than 200°C, and then This is achieved by providing a method for manufacturing a semiconductor device, which is characterized in that the wafer is subsequently washed with water, or by spraying water vapor at a temperature of 100°C or more and less than 200°C on the wafer after the above-mentioned trial etching. -ζ is also achieved each time the wafer is cleaned.

(6) Examples of the invention Hereinafter, embodiments of the present invention will be explained in detail with reference to the drawings.

The inventor of the present application has determined the amount of residual chlorine immediately after the tri-etching using the above-mentioned chlorine-based reaction gas by using fluorescent X.
It was determined by line analysis and the amount was set as 100.

The wafer after dry etching is exposed to nitrogen (N2).
When the amount of residual chlorine was measured by placing it in a gas-filled furnace at 100° C. for 5 minutes, the amount was reduced to 50, half of that in the previous example (100).

Continuing - After placing the C wafer on the spinner and cleaning the wafer with pure water for one time, the amount of residual chlorine was determined by the above setting.
It was recognized in 6(II) that the temperature in the furnace was 100° C.;

Therefore, in the method of the present invention, the principle obtained from the above experiment is applied, and immediately after tri-etching using a chlorine-based reactive gas, the wafer is heated to a temperature that does not cause any change in the resist. C. The wafer is washed with water. Since the resist used as a mask for etching the wafer usually softens and collapses at about 200°C, it has been demonstrated that the wafer can be heated to less than 200°C, preferably to about 180°C.

In the first embodiment of the present invention, a wafer that has been subjected to I-writing is placed in a furnace maintained at 180°C for 1 to 5 minutes, filled with N2 gas, and then subjected to tracing. The 1-degree spinner is used to clean the 1-degree wafer with pure water.

The heating of the wafer in the furnace continues for slightly more than one minute, since one minute is rather short. If rinsing takes 1 minute, removing residual chlorine takes just over 2 minutes, which is a significant reduction in time compared to the time required in the prior art. Moreover, when the amount of residual chlorine on the wafer was measured, it was 15 compared to the above-mentioned set value of 100.
It was confirmed that the amount of residual chlorine was 1/6 or more lower than Zunawara.

Based on the first embodiment, the inventor of the present application has determined that if the wafer is heated to a temperature within the above range and then washed with pure water to reduce the amount of residual chlorine, then the wafer after the treatment should be washed with the O1j description. I suspected that a similar effect could be produced by injecting water vapor (because hot water above 100°C and below 200°C cannot be heated), so I conducted an experiment based on this idea.
Good results were obtained as in the case of the first example. Thus, in the second embodiment of the present invention, instead of placing the wafer in a 180 DEG C. furnace, the dry-etched wafer 11 marked iji+ is immediately placed on the spinner 12 shown in FIG. Spinner 12 is heated to 100°C (not shown)
It has a built-in heater with a heating capacity of ~200°C to keep the wafer warm. Spinner for example 110
Rotates at 00 rpm, from nozzle 13 to 100℃ or more 200
Water vapor heated to a temperature within a range of 1&i is blown toward the wafer 11. After blowing this high-temperature water without air for 1 minute, we measured the amount of residual chlorine on the wafer and found that 1)
A value of -(15) was observed with respect to the set value of 100 as shown in 11, indicating that the amount of residual chlorine had significantly decreased as in the first example.

Subsequently, in the next process, the resist is removed using the conventional anosink technique, and the upper steps such as forming an insulating film are performed. Whether to carry out the first or second embodiment in forming the wiring body is determined depending on the wafer process that has been applied to the wafer up to that time, the type of semiconductor device, etc. , the temperature of the water vapor, etc. are selected as appropriate, keeping in mind the type of dry etching described in 111.

(7) Effects of the invention As explained in detail above, according to the performance of the present invention, it is possible to significantly reduce the amount of residual chlorine in Ueno 1 in a shorter time than with the conventional technology, and This is extremely important for improving the yield and product reliability of semiconductor device manufacturing, which is required.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing worm-eaten parts of the beta wiring body, and FIG. 2 is a perspective view showing a spinner for carrying out the powerful operation of the present invention. 1--insulation, 2-β wiring body, 3-resist film,
11- Wafer, 12- Spinner, ■3- Nostle No. 11 Fig. 2 2222: A, +2

Claims (1)

[Scope of claims]
A method for manufacturing a semiconductor device, which comprises heating the wafer to a temperature of .degree. C. or more and less than 200.degree. C., and then cleaning the wafer with water. (2) On the wafer after the trial etching, 100
2. The method of manufacturing a semiconductor device according to claim 1, wherein the wafer is cleaned by spraying water vapor at a temperature higher than or equal to 200°C.