JPH02238620A - Selective growth of silicon film - Google Patents

Abstract

PURPOSE:To relax a control operation of a gas composition by a method wherein an inner shell of a gas containing silicon is excited by using a synchrotron radiation beam and silicon ions are produced. CONSTITUTION:Inner shells of a gas containing silicon are excited by using a synchrotron radiation beam; silicon ions are produced. The silicon ions are brought into contact with a substrate having a region 1 composed of silicon at its outermost surface and a region composed of silicon oxide; the silicon is deposited on the silicon region 1; at the same time, the silicon oxide region is etched; a silicon film 3 is grown selectively. Thereby, a selective growth operation is realized by using a single gas; a gas composition can be controlled easily; it is possible to easily control a growth condition.

Description

Detailed Description of the Invention (Summary) The present invention relates to a method for selectively growing a silicon film, and an object of the present invention is to provide a method for selectively growing a silicon film in which control of gas composition is significantly reduced. A step of generating silicon ions by excitation of the inner shell with synchrotron radiation light, and bringing the silicon ions into contact with a substrate having a region made of silicon and a region made of silicon oxide on the outermost surface, The method includes a step of depositing silicon on the silicon oxide region and etching the silicon oxide region at the same time.

[Industrial application field]

The present invention relates to a method for selectively growing a silicon film.

[Conventional technology]

In recent years, in the manufacture of semiconductor devices, selective growth has been carried out in which, for example, a silicon film is grown only on exposed areas of a silicon substrate and not on other areas (for example, areas covered with silicon oxide). It is. Selective growth has a great advantage in shortening the manufacturing process because it allows the necessary separation between elements while growing the silicon film.

Conventionally, selective growth has been performed by adding HCβ gas to SitlzCI2z+H2, which is a source gas used for growing a silicon film. However, in order to grow a silicon crystal film with good film quality and selectively grow only the silicon crystal film, the composition of the multi-component mixed gas (especially HCI! Since it is necessary to extremely strictly control the amount of gas added, a great deal of burden is unavoidable for this control in the actual manufacturing process.

[Problem to be solved by the invention]

An object of the present invention is to provide a method for selectively growing a silicon film in which control of gas composition is significantly reduced.

[Failure to solve the problem]

The above object, according to the present invention, includes a step of generating silicon ions by inner-shell excitation/U of a silicon-containing gas with synchrotron radiation, and a step of generating silicon ions on the outermost surface with a region made of silicon and a region made of silicon oxide. A method for selectively growing a silicon film, comprising the step of depositing silicon on the silicon oxide region and simultaneously etching the silicon oxide region by bringing the silicon ions into contact with a substrate having a silicon oxide region. Ru.

In the present invention, a gas containing silicon as a constituent element (for example, S i II a . S i 2 I1 6, etc.)
Silicon ions (Si') are produced by irradiating them with highly engineered inert light such as Synchro 1 to Ron synchrotron radiation.
However, for example, a silicon film is selectively grown by depositing a silicon film in the exposed region of the silicon substrate and etching the silicon oxide in the region covered with silicon oxide.

? Example] FIG. 1 shows an example of a silicon film selective growth apparatus using synchrotron radiation excitation for carrying out the method of the present invention. SiH. Alternatively, si2116 gas (which may be diluted with +12, f{e, etc.) is flowed into the reaction chamber. The reaction pressure is not constant depending on the growth rate and light intensity, but is approximately in the range of 1.0'' Torr to 1 Torr. Synchrotron radiation is produced by SiHn and Si2It.
The energy light (
approximately 100 to 150 eV). Under these conditions, as shown in Figure 2(a), by irradiating a silicon substrate partially covered with silicon oxide with synchro 1.ron synchrotron radiation, Si' ions are generated near the substrate surface, and a second As shown in Figure (b), a Si film is deposited in the exposed area of Si, and at the same time, in the area where Si2 is present, SiO is generated by the following reaction: SiO■-1-Si'' →2SiO↑, and this evaporates. An enching reaction occurs.

〔Effect of the invention〕

According to the present invention, since selective growth can be achieved using a single gas, it is extremely easy to control the gas composition and the growth conditions. Furthermore, since chlorine-based gas is not used, it is possible to grow a high-quality film with less contamination of impurities, and since light energy rather than thermal energy is used, growth can be performed at low temperatures.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of an apparatus for carrying out the method for selectively growing a silicon film according to the present invention, and FIGS. 2(a) and (b) show a process for selectively growing a silicon film according to the present invention. FIG. 1... Silicon substrate, 2... Silicon oxide film,
3...Silicon film.

Claims (1)

[Claims] 1. A step of generating silicon ions by exciting the inner shell of a silicon-containing gas with synchrotron radiation, and a substrate having a region made of silicon and a region made of silicon oxide on the outermost surface. A method for selectively growing a silicon film, comprising the steps of depositing silicon on the silicon region and simultaneously etching the silicon oxide region by contacting the silicon ions.