JPS60236214A - Laser cvd method - Google Patents

Abstract

PURPOSE:To economically form a film within a minute short period by allowing growth of a film at the desired region on a substrate where a nucleus is formed by irradiation of ultraviolet ray through irradiation of visible laser beam to such region in a reaction chamber where a process gas is supplied. CONSTITUTION:Pressure within a reaction chamber is set adequately by opening an exhaustion port 5 and adequately setting supply of gas from a gas cylinder 2 and a substrate 10 is irradiated with the ultraviolet ray withing a short period (about several minutes) from an ultraviolet ray source 6 through a window 7A. Irradiation of such ultraviolet ray realizes formation of a very thin film or process gas (nucleus for growth of film) on the substrate. Next, a holder 9 is moved so that the substrate 10 is placed just under a window 7B by means of a holder moving mechanism 11. Here, the laser beam is focused to the desired position on the substrate 10 from a laser source 8 through the window 7B for irradiation for very short period (about several seconds) in accordance with thickness of film. This irradiation allows the growth of film because the laser energy is absorbed by the nucleus, only at the area where is irradiated with the visible laser beam.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a laser CVD 7Jh with shortened nucleation time.
Regarding the law.

Recently, CVD (Cl1ellICal V apor
Film formation using the D (!pO3!1ion) technology is being actively carried out. One of the best CVD methods 4.1. Provis gas is flowed into a reaction chamber in which a plate is placed, and the gas is thermally dissociated and adsorbed onto the surface of the plate to grow a film on the plate.
There is a problem with film formation. Also, B L1t? A plasma CVD method in which plasma is generated by applying direct current or high frequency EE to an electrode placed in a reaction chamber in which gas is introduced, and ionized gas particles are attached to the substrate 1.
lfi, but the ions in the Zolazun or 1. There is a problem in that the properties of the film deteriorate due to the presence of the bamboo particles in the film.

Therefore, C1 is a CV without such problems I) fJ method -
(1.: When the process gas is placed in the reactor, / J is irradiated with laser beam or ultraviolet light / light in the direction of the substrate to avoid photo-dissociation of the gas, and the photo-dissociation /, = gas Particles are treated differently (light CV l made to cause NJR)
The fJ method is being considered. Among the optical CVDrj methods, those using laser beams are called laser CV Drj methods.
7) *Use an ultraviolet lamp and cover it with the CVD method.
Weight (laser CV D 7J > person) (laser wavelength A-ta) 2 Since it can be narrowed down, Ic, l-8t
, J (if 81) It is said to be effective for repairing device wiring and semiconductor masks11.

However, there is a problem with this tr Rayleigh CV I) fJ method. In particular, when the visible light sea 1F' ray is irradiated to the base, a film is immediately formed on the 1F, square problem (
In the case of a long period of time (more than several tens of minutes), film growth does not occur. The length of this period is not constant depending on the type of wrestling gas, the surface condition of the substrate (for example, the degree of moisture adhesion on the surface of the substrate), the wavelength and power of the laser beam, etc.

The present invention is aimed at solving such problems.

The length of the period during which the film does not grow after laser beam irradiation varies depending on the type of process gas, the surface condition of the substrate (for example, the degree of moisture adhesion on the substrate surface), the power of the laser beam, etc. Regardless of these conditions, in the laser CVD method, there is a period during which the film does not grow for a while after laser beam irradiation.

We considered what is happening in the part of the substrate that is hit by the laser beam during this 1v1 interval, and found that the seeds (nuclei) of the film necessary for film growth are generated on the root surface. Confirmed by electron microscope observation. Therefore, the period will hereinafter be referred to as the nucleation period. Now, when considering why the nucleation period is long in the laser CVD method, it seems that since the visible light laser has a long wavelength, it is generally difficult to be absorbed by the wrestling gas, and it takes time for the generation of nuclei.

Therefore, in the present invention, in the pre-process of growing a film using the visible light laser method, we have developed a method that uses a chemical vapor deposition method (CVD) that has extremely good absorption of blue gas and can form nuclei in a very short time.
The present invention provides a method in which a film is grown on a substrate on which the nucleation is performed immediately after the nucleation step by a visual laser CVD method.

Although there is C+1 light in the ultraviolet region, this light source is much more expensive than the ultraviolet light source.

The attached drawing shows a visible light laser CVD54P as an embodiment of the visible light laser+J' CVD method of the present invention. In Figure 11, which is a schematic diagram, 1 (J reaction chamber, gas supply port 3 connected to gas cylinder 2,
It includes an air vent 5, a window 7A that guides ultraviolet rays from an ultraviolet light source 6 into the reaction chamber, and a window 7B that guides a laser beam from a laser light source 8 into the reaction chamber. 9 A substrate holder on which a beam plate 10 is placed, and the holder is moved by a holder moving machine 4 provided outside the reaction chamber.
It is possible to move j4 in a second-order redundant manner by f1511. 12G
, L laser optical system, consisting of a lens that focuses the laser beams from the laser beams 1 and 1Iri8, and a mirror that controls the irradiation position of the laser beams.

In such an apparatus, the holder 9 is moved by the holder moving mechanism 9 so that the substrate 10 is directly under the window 7A. First, 1) the inside of the reaction chamber 1 is made into a high vacuum using the 1-air means 4, and the exhaust port 5 is closed. In this state, a process gas (e.g., a mixed gas containing N2 gas and 3i and 14 gases) is supplied into the reaction chamber from the gas cylinder 2, and a force of about several Torr is applied inside the reaction chamber. . In this state, the surface of the substrate 10 is sufficiently coated with Dt? adsorbs gas. Next, the pressure inside the reaction chamber is adjusted to an appropriate level by appropriately setting the gas supply Φ from the gas cylinder 2, and ultraviolet rays are emitted from the ultraviolet light source 6 through the window 7△. The substrate 10 is irradiated for a short period of time (eg, several minutes). This ultraviolet irradiation causes the substrate 1 to be coated with extremely thin (100 Å or less) process gas Mu (IP!).
form a nucleus for growth). Next, the holder movement FM
The holder 9 is moved by the mechanism 11 so that the substrate 10 is directly under the window 17B. Here, a laser beam from the laser light source 8 is focused on an arbitrary position on the substrate 10 through the window 7B and irradiated for a very short time (several seconds) depending on the film thickness. As a result of the irradiation, the laser L energy is absorbed by the nucleus in the area irradiated with the visible laser beam, and particles grow.

In the above embodiment, the substrate is moved to the laser beam irradiation position after being irradiated with ultraviolet rays. (Although it is designed to irradiate a laser beam, it is also possible to arrange Jl at the laser irradiation position from the beginning and irradiate the laser beam while irradiating ultraviolet rays.

According to the present invention, a nucleus for film growth is formed in the base (long) using short wavelength ultraviolet rays, and a visible laser beam is irradiated at the (T foot position of the substrate). Since the film is formed in such a manner that the film can be formed at low cost and in a very short time, the nucleation period by visible light laser CVD becomes approximately zero according to the present invention.

[Brief explanation of the drawing]

The attached drawings are one embodiment of the laser CV Dij method of the present invention. ) There is an outline of each device. 1; Friendship room 2: Gas cylinder 4: IJI-T stage 6: Ultraviolet light source 7A, 713: Window 8-1f light source 9: Heavy plate holder 10: Substrate 11: Holder moving mechanism 12: Rayleigh optical system patent applicant [Representative of 1Pon Electronics Co., Ltd. 9 Fuji - Husband

Claims (1)

[Claims] 11 In reaction V where a process gas has been introduced, a visible laser beam is irradiated onto a location on the substrate where a nucleus has been formed by ultraviolet irradiation. Method.