JPS5844723A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To obtain an element isolation region by hydrolyzing raw material, the principal ingredient thereof is SiCl4, by an oxyhydrogen flame and depositing the particulates of SiO2 onto a semicondutor substrate and sintering the particulates. CONSTITUTION:SiCl4 at the rate of 100cc/min, H2 at the rate of 2,000cc/min and O2 at the rate of 3,000cc/min are forwarded to a burner, and the particulates of SiO2 are deposited onto the surface of the semiconductor substrate 1, to which grooves 2 are formed, by approximately 300mum thickness. Approximately six min is required for said process. When the whole is treated for 120min at 1,200 deg.C, transparent hard glass 5 is formed. When the back of the substrate is processed up to desired thickness, the substrate with the isolation region is completed. This method needs no thermal oxidation, and further the velocity of growth is faster only by one figure. The quantity of processing can easly be measured optically when the substrate is processed from the backs of the grooves because the transparent holder 5 is shaped after sintering.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a semiconductor device using a dielectric isolation method, and more specifically, the present invention relates to a method for manufacturing a semiconductor device using a dielectric isolation method, and more specifically, a plurality of semiconductor crystal regions forming a high voltage circuit element are each made of a dielectric material. This article relates to a method for manufacturing a substrate having a structure embedded in the Y special holiday.

The conventional manufacturing method for this type of device is to form an etched groove in an isolation region on the surface of a semiconductor substrate, then form an oxide film in the groove by thermal oxidation, and then deposit polycrystalline silicon with a thickness of 600 to 400 μm. Since the holding body was formed by CVD, the growth rate of polycrystalline silicon was slow at about 3 to 5 μm/min, and furthermore, it was necessary to perform thermal oxidation for dielectric isolation.

In order to solve these drawbacks, this Komei has developed silicon tetrachloride (8
Fine particles of glass (5102) produced by flame hydrolysis of a raw material whose main component is 1C14) with an oxyhydrogen flame are deposited on a semiconductor substrate and then sintered by 1°.The drawings will be explained in detail below. .

FIG. 1 is an explanatory diagram of the principle of the manufacturing method of the present invention.

In the figure, 1 is a semiconductor substrate (single crystal substrate), 2 is an etched groove, 6 is a burner for spraying, and 4 is a flame.

FIG. 2 is a cross-sectional view of a semiconductor device formed according to the present invention. In the figure, 5 is transparent hard glass (holder)
It is.

In carrying out the manufacturing method of the present invention, a semiconductor substrate 1 in which etched grooves 2 are formed in separation regions is coated with S i Cl 4 as a main component (in addition, it is used to adjust the expansion coefficient of glass, the temperature required for sintering, etc.). For example, B2O3, P2O5, etc. may be added.) A raw material containing oxyhydrogen flame is sprayed onto the groove forming surface from a bar 6 to deposit fine glass particles and form a porous glass holder. Form. Furthermore, 1000
When heated at a high temperature of ~1600° C., the volume of this porous glass holder decreases to about 600° C. and becomes transparent hard glass.

Next, an example will be explained.

For spraying, apply S i (-1!) to burner 6 (see Figure 1).
4 at 100CC/min, [I2 at 2000CC/min, 02
was fed at a rate of 3000 cc/min to deposit glass (SiO2) fine particles on the surface of the semiconductor substrate 1 provided with the etched grooves. Approximately 6 minutes was sufficient to form 600 μm of glass on a 6 inch semiconductor substrate.

That is, the growth rate of glass is about 0.5 g/min. After that, heat treatment was performed, but the heat treatment time was at a temperature of 12
At 00°C, it took about 120 minutes. After sintering,
The surface opposite to the surface on which the transparent hard glass was formed was processed until the desired thickness was reached, and a substrate with a separation region for forming a high-voltage element was constructed.

As explained above, in the manufacturing method of the present invention, since the dielectric S r 02 is directly attached to the substrate, a thermal oxidation step is not necessary, and the growth rate is improved by one order of magnitude. Furthermore, since a transparent holder is formed after sintering, there are advantages such as the ability to optically easily measure the amount of processing during the subsequent processing step from the direction opposite to the groove. □

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the principle of the manufacturing method of the present invention, and FIG. 2 is a sectional view of a semiconductor device formed according to the present invention. 1... Semiconductor substrate 2... Etched groove 6... Burner for spraying 4... Flame 5... Hard glass (holding body) Patent applicant Junnosuke Nakamura, patent attorney representing Nippon Telegraph and Telephone Public Corporation

Claims (1)

[Claims] After forming etched grooves in the area to be separated on the surface of the semiconductor substrate, a raw material containing 5IC14 as a main component is blown onto the surface of the substrate on the side where the grooves are to be formed together with an oxyhydrogen flame, so that the glass fine particles produced by the flame hydrolysis reaction are formed into a layer. 1. A method for manufacturing a semiconductor device, comprising: depositing the substrate to form a porous base material, and then performing high-temperature heat treatment at 1000° C. or higher to sinter the porous base material to form a holder for the substrate.