JP2835095B2 - Laser CVD equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a laser CVD (Chemical Vapor Depositi).
on) It relates to improvement of the device.

(Prior Art) As shown in FIG. 2, a conventional laser CVD apparatus has a reaction gas inlet 3 in a vacuum chamber 2 in which a substrate 1 is disposed.
, A vacuum exhaust port 4 and a laser introduction window 5, and an inert gas introduction port 6 is further provided near the laser introduction window 53. A laser oscillator 7 and a lens system 8 are arranged in the atmosphere around the vacuum chamber 2.

In such a laser CVD apparatus, the laser light generated by the laser oscillator 7 is converged by the lens system 8 and then passes through the laser introduction window 5 and is irradiated on the substrate 1. The reaction gas introduced into the vacuum chamber 2 from the reaction gas inlet 3 is excited,
Activation energy is provided. Then, the reaction gas given the activation energy reacts with the substrate 1 to form a thin film on the surface of the substrate 1.

However, at this time, the reactive gas given the active energy not only reacts with the substrate 1, but also reacts with other parts in the vacuum chamber 2, for example, the laser introduction window 5, and deposits a thin film there. Attempts to form and contaminate.

However, when the area of the laser introduction window 5 is small, the inert gas introduced from the inert gas introduction port 6 forms a flow over the entire surface of the laser introduction window 5. Is prevented from reaching the laser introduction window 5, no reaction or the like occurs in the laser introduction window 5, and contamination due to the formation of a thin film is prevented.

(Problems to be Solved by the Invention) In the conventional laser CVD apparatus, when the area of the laser introduction window 5 is small as described above, the activation energy is given by the flow of the inert gas flowing over the entire surface of the laser introduction window 5. The reaction gas is prevented from reaching the laser introduction window 5 and contamination due to the formation of a thin film at the laser introduction window 5 is prevented.

However, when the diameter of the substrate 1 is increased, the area of the laser introduction window 5 must be increased accordingly. If the area of the laser introduction window 5 is increased, the inert gas introduced from the inert gas introduction port 6 cannot form a flow over the entire surface of the laser introduction window 5,
No flow is formed on some surfaces of the laser introduction window 5. Therefore, the laser introduction window 5 in which the reactive gas given the active energy does not form the flow of the inert gas.
, Where a reaction occurs and the like, and a thin film is formed to cause contamination, thereby causing problems such as making continuous operation impossible.

An object of the present invention is to solve the conventional problems and to provide a laser CVD apparatus which enables continuous operation while preventing contamination due to formation of a thin film at a laser introduction section even when a substrate has a large diameter. It is in.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a method in which a reaction gas is excited by a laser beam generated by a laser oscillator and activated energy is applied to the reaction gas to thereby arrange the reaction gas in a vacuum chamber. In a laser CVD apparatus that forms a thin film on the surface of a substrate, a lens system that converges or diverges the laser light is disposed inside, a laser introduction unit that flows an inert gas around the lens system, and this laser introduction unit. A drive system, such as a bellows, which is provided between these for connecting the vacuum chamber and which expands and contracts the laser introduction unit by expanding and contracting, and a laser beam immediately after being generated by the laser oscillator in the lens of the laser introduction unit And at least a part of the laser light converged or diverged by the lens system of the laser introduction section. And an orifice to be passed.

(Operation) In the laser CVD apparatus of the present invention, the laser light immediately after being generated by the laser oscillator is guided by an optical fiber to the lens system of the laser introduction part, where it is converged or diverged, passes through the orifice, and irradiates the substrate. However, when the laser introduction unit is moved using a drive system such as a bellows, the lens system also moves, and the distance between the substrate and the lens system changes. Laser intensity, irradiation area, etc. change. In this way, the laser beam irradiated on the substrate excites the reactive gas and gives it activation energy, thereby reacting with the substrate and forming a thin film on the surface of the substrate. Attempts to form a thin film on other parts of the vacuum chamber. However, the inert gas flows around the lens system in the laser introduction part while being easily retained by the presence of the orifice, and the inert gas flows into the vacuum chamber after passing through the orifice. The reaction gas excited by the laser beam and given the activation energy is prevented from flowing in the direction of the lens system. For this reason, contamination due to the formation of a thin film does not occur in the lens system.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. In FIG. 1, a vacuum chamber 2 in which a substrate 1 is disposed is provided with a reaction gas inlet 3 and a vacuum exhaust port 4. In addition, a laser introduction unit 10 is connected to the vacuum chamber 2 via a drive system 9 such as an extendable bellows, and the laser introduction unit 10 can be moved by the drive system 9. In the laser introducing unit 10, a lens system 8 for converging or diverging a laser beam is disposed. Further, the laser introducing section 10 is provided with an inert gas inlet 6, and the inert gas introduced into the laser introducing section 10 from the inert gas introducing port 6 flows around the lens system 8. A laser oscillator 7 is arranged in the atmosphere around the vacuum chamber 2, and the laser oscillator 7 and a lens system 8 in a laser introducing unit 10 are provided.
An optical fiber 11 is provided therebetween. Therefore, the laser light immediately after being generated by the laser oscillator 7 passes through the optical fiber 11 and passes through the lens system 8 in the laser introduction unit 10.
To be converged or diverged by the lens system 8. The laser introduction unit 10 has an orifice 12 provided on the vacuum chamber 2 side near the lens system 8 in addition to the lens system 8. Therefore, at least a part of the laser light converged or diverged by the lens system 8 passes through the orifice 12,
The substrate 1 is irradiated. In addition, the inert gas flowing around the lens system 8 flows through the orifice 12 and flows into the vacuum chamber 2 while being easily retained in the laser introduction unit 10 due to the presence of the orifice 12.

 Next, the operation of the embodiment will be described.

The laser light immediately after being generated by the laser oscillator 7 is guided to the lens system 8 in the laser introducing unit 10 through the optical fiber 11 and converged or diverged by the lens system 8.
The laser beam passes through the orifice 12 and irradiates the substrate 1.
Is moved, the lens system 8 also moves, and the distance between the substrate 1 and the lens system 8 changes. Accordingly, the laser intensity, the irradiation area, and the like at the substrate position change. Therefore, even if the diameter of the substrate 1 is increased, it is not necessary to increase the area of the lens system 8.

The laser beam irradiated onto the substrate 1 in this manner excites the reaction gas introduced into the vacuum chamber 2 from the reaction gas inlet 3 and gives active energy to the reaction gas. By performing a reaction or the like, a thin film is formed on the surface of the substrate 1.

However, when forming a thin film on the surface of the substrate 1,
The reaction gas excited and given the active energy reacts with other parts other than the substrate 1 in the vacuum chamber 2 and the like,
It tries to contaminate by forming a thin film there.

However, the inert gas flows around the lens system 8 in the laser introduction unit 10 while being easily retained by the presence of the orifice 12.
After flowing through, the reaction gas excited by the laser beam and given the active energy is prevented from flowing in the direction of the lens system 8. Therefore, in the lens system 8, contamination due to the formation of the thin film is prevented.

In addition, this invention is not limited to the said Example,
Various design changes are possible based on the technical idea of the invention. Furthermore, although the above embodiment of the present invention relates to a laser CVD apparatus, if the lens system 8 in the laser introduction unit 10 is moved in three-dimensional directions and used, it can also be used for drawing an etching pattern or the like. .

(Effects of the Invention) According to the present invention, when the distance between the substrate and the lens is changed by moving the laser introduction unit using a drive system such as a bellows as described above, the laser intensity at the position of the substrate is accordingly changed. Since the irradiation area and the like change, the area of the lens system does not need to be increased even if the diameter of the substrate is increased. In addition, the inert gas flowing while stagnating around the lens system flows into the vacuum chamber after passing through the orifice, so that the reactive gas excited by laser light and given active energy flows in the direction of the lens system. Will be blocked. For this reason, contamination due to the formation of a thin film in the lens system of the laser introducing section is prevented.
Furthermore, by preventing contamination due to the formation of a thin film,
Continuous operation of the device becomes possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a laser CVD apparatus according to an embodiment of the present invention. FIG. 2 is a configuration diagram showing a conventional laser CVD apparatus. In the drawing, 1 ... substrate 2 ... vacuum tank 3 ... reaction gas inlet 6 ... inert gas inlet 7 ... laser oscillator 8 ... lens system 9 ... drive system 10 ... laser introduction unit 11 ... ... optical fiber 12 ... orifice In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

(57) [Claims] 1. A laser CVD apparatus which excites a reaction gas with a laser beam generated by a laser oscillator and gives activation energy thereto to form a thin film on a surface of a substrate placed in a vacuum chamber. A lens system for convergence or divergence is disposed inside, and a laser introduction unit for flowing an inert gas around the lens system; and a laser introduction unit is provided between the laser introduction unit and the vacuum tank to connect the laser introduction unit to the vacuum tank. A drive system such as a bellows that moves the laser introduction unit by expanding and contracting, an optical fiber that guides the laser light immediately after being generated by the laser oscillator to the lens system of the laser introduction unit, and converges by the lens system of the laser introduction unit Or an orifice for passing at least a part of the diverged laser light. CVD apparatus.