JPH0276228A - Device for cleaning semiconductor substrate - Google Patents

Abstract

PURPOSE:To improve uniformity of ultrasonic energy density in a cleaning tank by providing a plurality of ultrasonic oscillators in parallel which generate cavitation phenomena through ultrasonic wave in a cleaning solution in the inside of the tank to a sidewall of the tank wherein a semiconductor substrate is immersed. CONSTITUTION:A cleaning tank is constituted in an internal and external double structure of a inner tank 2 and an outer tank 3, and provided with a plurality of ultrasonic oscillators 1, 1... in parallel at a bottom of the inner tank 2 in a range not less than a half of a bottom area of the inner tank 2. Energy density of ultrasonic waves 5 inside the cleaning tank can be thereby made larger than that in the case of a single oscillator. Therefore, even if one or two units of oscillators 1 deteriorate, the ultrasonic energy density can be maintained only with a little change of the ultrasonic energy density in the whole tank. According to this constitution, it is possible to generate cavitation phenomena generated inside a cleaning tank uniformly, and ultrasonic energy density can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cleaning device for silicon substrates for semiconductor device manufacturing boxes.

[Conventional technology]

Conventionally, as shown in FIG. 3, a cleaning device for silicon substrates used in the manufacture of semiconductor devices is equipped with a dual-layered cleaning tank consisting of an inner tank 2 and an outer tank 3, and the inner tank 2 is filled with a cleaning liquid 6. A heater 4 is installed between the inner and outer tanks 2 and 3, and a single ultrasonic vibrator 1 is installed at the bottom of the inner tank 2. was used to clean the substrate by causing a cavitation phenomenon.

[Problem to be solved by the invention]

In the conventional silicon substrate cleaning equipment mentioned above, the ultrasonic vibrator is attached individually to the bottom of the cleaning layer, so the cavitation phenomenon caused by the ultrasonic waves, which is an indicator of the degree of cleaning effectiveness, varies greatly depending on the position in the cleaning tank. This has the disadvantage that the ultrasonic energy intensity within the tank is not uniform. Furthermore, if the oscillator is made larger in order to improve the uniformity within the chamber, the ultrasonic energy intensity increases locally, causing crystal defects that are fatal to the semiconductor device. Another drawback is that the ultrasonic energy intensity is determined by the tone of one ultrasonic transducer.

An object of the present invention is to provide a cleaning device that solves the above problems.

[Differences between the invention and the prior art]

Compared to the conventional cleaning device described above, the present invention has the difference that it improves the uniformity of the ultrasonic energy intensity within the bath.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a cleaning apparatus for cleaning semiconductor substrates, in which a plurality of ultrasonic vibrators are installed on the wall surface of a cleaning tank in which the semiconductor substrate is immersed, to generate a cavitation phenomenon by ultrasonic waves in the cleaning liquid in the tank. They are deployed in parallel.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

(Example 1) FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

In the figure, the cleaning tank has an inner and outer double structure with an inner tank 2 and an outer tank 3, and a heater 4 is installed between the inner and outer tanks 2 and 3.

Furthermore, a plurality of ultrasonic transducers 1°1...
・Deploy in parallel. The plurality of ultrasonic transducers 1°1...
is installed over 172 or more pronations of the bottom area of the inner tank 2.

In the present invention, since a plurality of ultrasonic transducers 1, 1... are installed in parallel on more than 1/2 of the bottom area of the cleaning tank, the energy of the ultrasonic waves 5 in the cleaning tank is as shown in FIG. The strength can be made larger than that of a single oscillator, even if 1
Even if one or two vibrators deteriorate, the ultrasonic energy intensity in the entire tank can be maintained with only a small change, and as shown in Figure 4, cavitation that occurs in the cleaning tank can be prevented. Phenomena can occur uniformly.

In addition, as shown in FIG. 6, since the present invention is equipped with a plurality of ultrasonic transducers, the particle removal rate on the substrate with respect to the deterioration life of the ultrasonic transducers is compared with the deterioration of the ultrasonic transducers by the conventional device. The particle removal rate on the substrate can be improved over the lifetime.

(Example 2) FIG. 2 is a configuration diagram showing a second embodiment of the present invention.

In this embodiment, a bottom 2a and a side surface 2b of an inner tank 2 forming a cleaning tank are shown.
A plurality of ultrasonic transducers 1.1 are arranged three-dimensionally.
This has the advantage that the cavitation phenomenon in the cleaning tank can be made more uniform than before.

〔Effect of the invention〕

As explained above, the present invention makes it possible to uniformly cause the cavitation phenomenon occurring in the cleaning tank within the tank, and furthermore, it becomes possible to increase the ultrasonic energy intensity compared to the conventional method. Furthermore, even if one or two ultrasonic vibrators deteriorate, the other vibrators compensate for this and maintain the ultrasonic energy intensity of the metal body within the tank with only a small change.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing a first embodiment of the present invention, Fig. 2 is a block diagram showing a second embodiment of the present invention, and Fig. 3 is a conventional semiconductor device @
FIG. 4 is a diagram showing the uniformity of the cavitation phenomenon in the tank in the cleaning device of the present invention, and FIG. 5 is a diagram showing the uniformity of the cavitation phenomenon in the cleaning device of the present invention. Figure 6, which is a diagram showing the relationship between sonic energy intensity and the number of transducers, shows the difference in the particle removal rate on silicon substrates between the conventional cleaning device and the cleaning device of the present invention with respect to the deterioration life of the ultrasonic vibrator. FIG. l...Ultrasonic vibrator 2...Inner tank 3 of cleaning tank
・・・Outer tank of cleaning tank

Claims (1)

[Claims] (1) A cleaning device for cleaning semiconductor substrates, characterized in that a plurality of ultrasonic vibrators are arranged in parallel on the wall of the cleaning tank in which the semiconductor substrate is immersed, which generates cavitation phenomenon due to ultrasonic waves in the cleaning liquid in the tank. Cleaning equipment for semiconductor substrates.