JPH02185035A - Method of depositing film - Google Patents

Abstract

PURPOSE:To prevent adhesion onto a film of the particles of a product, etc., in a liquid phase, and to improve the reliability of the deposit film by ultrasonic- vibrating a reaction solution or a semiconductor substrate when the film is liquid-phase deposited onto the semiconductor substrate. CONSTITUTION:An ultrasonic vibrating tank 1 functioning as a thermoplastic chamber in combination is filled with water 2, and a reaction tank 3 is installed into water. The reaction tank 3 is filled with a reaction solution 4, and a semiconductor wafer 5 is supported into the reaction solution 4 by a holder 6. When an SiO2 film is deposited onto the semiconductor wafer 5 by using the device, H2SiF6 is employed as the reaction solution 4, ultrasonic waves are generated from the ultrasonic vibrating tank during a time when the wafer 5 is dipped into the solution 4, and the solution is given ultrasonic waves. Accordingly, the coverage of silica particles is reduced on the wafer 5, thus improving the reliability of the SiO2 film.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a method for manufacturing a semiconductor device in which a film is deposited in a liquid phase on a semiconductor substrate.

(Prior Art) A liquid phase deposition method is used as one method for forming a film on a semiconductor substrate. As an example of the liquid phase deposition method, the following reaction is used to deposit 8i0. There are methods for depositing films.

H,5iFs +2H,0→Smu0. ↓+aHF However, with this method, many particles of reaction products generated in the liquid adhere to the membrane surface, and because the particles and the membrane have the same composition, it is difficult to remove only the particles in post-treatment. Ta. That is, in the example of the above reaction formula, the 8i0. !
When the silica particles adhere to IX and the substrate is taken out to the atmosphere, the silica particles become Sin! It hardens on the film and is difficult to remove, deteriorating the reliability of the film on the substrate.

(Problems to be Solved by the Invention) As mentioned above, when forming a desired film on a substrate by conventional liquid phase deposition, unnecessary particles such as silica generated in the liquid phase are deposited on the film. It was difficult to remove the particles.

The present invention eliminates the drawbacks of the conventional liquid phase deposition method, and eliminates unwanted particles generated in the liquid phase from adhering to the film deposited on the substrate in the liquid phase. The purpose is to provide a method that also improves reliability.

[Structure of the invention]

(Means for Solving the Problems) The present invention is characterized in that when depositing a film on a semiconductor substrate in a liquid phase, the reaction solution or the semiconductor substrate is subjected to ultrasonic vibration.

(Function) According to the present invention, when a desired layer is deposited on a substrate such as a semiconductor in a liquid phase, when the reaction solution or the semiconductor substrate is ultrasonically vibrated, the particles generated in the liquid phase are It will no longer adhere to the membrane.

Specifically, for example, when introducing KSiO,[9 into the liquid phase of a silicon substrate H, 8j F. A large number of silica grains are present. On the other hand, on the substrate, Sin, which is much smaller than the silica grains and has a diameter of about 10 A, is precipitated by the reaction described above.

However, by applying ultrasonic vibration to the substrate or liquid phase, large silica particles can be
0. The silica grains that are difficult to adhere to the film and therefore exist on the 5ins film even when the substrate is removed from the liquid phase after film deposition are extremely reduced. Membrane reliability is improved.

(Example) First example An embodiment of the invention will be described with reference to the drawings.

FIG. 1 is a schematic diagram of an apparatus for explaining a first embodiment of the present invention. Ultrasonic vibration bath that also serves as a constant temperature bath (1)
is filled with water (2), and a reaction tank (3) is installed therein. The reaction tank (3) contains a reaction solution (4).
is filled and the semiconductor wafer (5) is placed in the holder (6).
) K is supported in the reaction solution (4).

Using this device, SiO is deposited on a semiconductor wafer (5).
! When depositing the film, H2SiF is used as the reaction solution (4).
While the wafer (5) is immersed in the solution (4), an ultrasonic wave is emitted from the ultrasonic vibration tank to impart ultrasonic waves to the solution. As a result, the amount of silica particles attached to the wafer (5) is significantly reduced compared to the conventional method, and
Membrane reliability has been improved.

Second Embodiment FIG. 2 is a schematic diagram of an apparatus for explaining a second embodiment of the present invention. The constant temperature reaction tank (7) contains a reaction solution (4
) is filled with H, Sip, in which a semiconductor wafer (5) is suspended and held by a holder (6a). The holder (6a) is an ultrasonic vibration device (8)
The semiconductor wafer (5) can be ultrasonically vibrated.

Even if ultrasonic waves are applied to the semiconductor wafer (5) itself in this way, the same effect as in the first embodiment can be obtained.

The present invention is not limited to the first and second embodiments described above; for example, the ultrasonic waves may be applied to the semiconductor wafer and the solution, and the solution may also be changed as appropriate depending on the film to be deposited. You may do so.

Further, a catalyst such as aluminum or boron may be mixed into the solution (41) to promote the deposition of the deposited film.

〔Effect of the invention〕

As explained above, according to the present invention, when depositing a deposited film on a semiconductor substrate in a liquid phase, particles such as products in one liquid phase do not adhere to the film, thereby improving the reliability of the deposited film.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an apparatus for explaining a first embodiment of the invention, and FIG. 2 is a schematic diagram of an apparatus for explaining a second embodiment of the invention. 1... Ultrasonic vibration bath that also serves as a constant temperature bath, 2... Water, 3
... Reaction tank, 4 ... Reaction solution, 5 ... Semiconductor wafer, 6.6a ... Holder 7 ... Constant temperature reaction tank, 8
...Temperature wave vibration device. Agent Patent Attorney Noriyuki Chika

Claims (3)

[Claims] (1) A film deposition method characterized in that when forming a deposited film on a semiconductor substrate in a liquid phase, ultrasonic vibrations are applied to the liquid phase or the substrate. (2) The semiconductor substrate is a silicon substrate, and when depositing the SiO_2 film on the substrate, H_2 is used as a liquid phase.
Claim 1 characterized in that a solution of 2SiF_6 is used.
Film deposition method as described. (3) The film deposition method according to claim 2, characterized in that a catalyst such as aluminum or boron is mixed into the solution.