METALORGANIC CHEMICAL VAPOR PHASE EPITAXY OR VAPOR PHASE DEPOSITION APPARATUS

Abstract

A Metalorganic chemical vapor phase epitaxy or vapor phase deposition apparatus, having a first gas source system, a reactor, an exhaust gas system, and a control unit, wherein the first gas source system has a carrier gas source, a bubbler with an organometallic starting compound, and a first supply section leading to the reactor either directly or through a first control valve, the carrier gas source is connected to an inlet of the bubbler through a first mass flow controller by a second supply section, an outlet of the bubbler is connected to the first supply section, and the carrier gas source is connected to the first supply section through a second mass flow controller by a third supply section, the first supply section is connected to an inlet of the reactor through a third mass flow controller.

Claims

1. A metalorganic chemical vapor phase epitaxy or vapor phase deposition apparatus comprising: a first gas source system; a reactor; an exhaust gas system; and a control unit, wherein the first gas source system has a carrier gas source, a bubbler with an organometallic starting compound, and a first supply section leading to the reactor either directly or through a first control valve, wherein the carrier gas source is connected to an inlet of the bubbler through a first mass flow controller via a second supply section, wherein an outlet of the bubbler is connected to the first supply section, wherein the carrier gas source is connected to the first supply section through a second mass flow controller via a third supply section, wherein the first supply section is connected to an inlet of the reactor through a third mass flow controller downstream after the connection to the outlet of the bubbler and after the connection to the third supply section, and wherein the gas-mixing system has a pressure sensor on the first supply section ahead of the third mass flow controller or on the second supply section or the pressure sensor is flange-mounted directly on the bubbler in order to determine the flow in the gas source by the mass flow regulators.

2. The apparatus according to claim 1, wherein the first supply section is connected to the exhaust gas system through a fourth mass flow controller downstream after the connection to the third supply section and ahead of the third mass flow controller.

3. The apparatus according to claim 1, wherein the control unit is designed to read out pressure values of the pressure sensor and to regulate one or more or all mass flow controllers of the gas-mixing system while taking into account pressure values that have been read out.

4. The apparatus according to claim 3, wherein the control unit is designed to regulate the first mass flow controller and/or the second mass flow controller and/or the fourth mass flow controller while taking into account a mass flow through the third mass flow controller.

5. The apparatus according to claim 1, wherein the first supply section has, parallel to a line section that contains the third mass flow controller, a line section with a pressure controller, wherein either the line section that contains the third mass flow controller or the line section of the first supply section that contains the pressure controller is shut off at a given time.

6. The apparatus according to claim 1, wherein a precursor of the bubbler is designed as a solid precursor.

7. The apparatus according to claim 1, wherein the flow in the gas source is determined solely by the mass flow regulators.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0054] FIG. 1 shows a view of an exemplary vapor phase epitaxy or vapor phase deposition apparatus,

[0055] FIG. 2 shows a view of an exemplary vapor phase epitaxy or vapor phase deposition apparatus, and

[0056] FIG. 3 shows a view of an exemplary vapor phase epitaxy or vapor phase deposition apparatus

DETAILED DESCRIPTION

[0057] The illustration in FIG. 1 shows a first example of a vapor phase epitaxy or vapor phase deposition apparatus 10.

[0058] The vapor phase epitaxy or vapor phase deposition apparatus 10 has a reactor 14, a control unit 18, at least one first gas source system 12, and an exhaust gas system 16.

[0059] It should be noted that the reactor 14 a is connected to the exhaust gas system 16 by means of a discharge section that is not shown.

[0060] The gas source system 12 is connected to the reactor 14 and to the exhaust gas system 16 through a first supply section Z1 and a first control valve 13.

[0061] In addition, the gas source system 12 has a carrier gas source 20 for a carrier gas T, for example H.sub.2 or N.sub.2, and a bubbler 22 with, e.g., a liquid precursor P , for example TMGa.

[0062] The carrier gas is conducted from the carrier gas source 20 to an inlet of the bubbler 22 through a second supply section Z2. The carrier gas T emerges from a pipe in the region of the bottom of the bubbler 22, and rises through the precursor P in the form of bubbles.

[0063] It should be noted that, in an embodiment that is not shown, the precursor P is also implemented as a precursor P in solid form, which is to say as a solid precursor P. In this case, the short and long pipe lengths can be swapped in their connections. In another embodiment, the bubbler 22 contains a heating coil, in particular in order to heat the solid precursor P to a specified temperature.

[0064] An outlet of the bubbler 22 is connected to the first supply section Z1 in order to conduct the emerging gas mixture, which is to say the carrier gas T enriched by the precursor P, from the bubbler 22 into the reactor 14.

[0065] In addition, the carrier gas source 20 is connected to the first supply section Z1 through a third supply section Z3 after the outlet of the bubbler 22. Preferably, the gases converge in a T-piece.

[0066] The gas stream from the carrier gas source 20 to the bubbler 22 through the second supply section Z2 can be regulated by means of a first mass flow controller F1 and the gas stream from the carrier gas source 20 to the first supply section Z1 through the third supply section Z3 can be regulated by means of a second mass flow controller F2.

[0067] Arranged in the first supply section downstream after the connection to the third supply section Z3 and before the first control valve 13 is a third mass flow controller F3.

[0068] In addition, a pressure sensor P1 is arranged on the first supply section Z1 or on the second supply section Z2 - drawn with dashed lines - or flange-mounted directly on the bubbler 22 - drawn with dashed lines.

[0069] It is a matter of course that the pressure sensor P1 is arranged on only one of the three positions. It should also be noted that the pressure sensor P1 and the mass flow controller are each connected to a control and analysis unit. The single control and analysis unit regulates the mass flow controllers to the specified values in accordance with the specifications of the control program in this case.

[0070] In the illustration in FIG. 2, another embodiment is shown. Only the differences from the illustration in FIG. 1 are explained below.

[0071] The gas source system 12 additionally has a fourth supply section Z4 with a fourth mass flow controller F4, wherein the fourth supply section connects the first supply section Z1 to the exhaust gas system 16, and for this purpose is connected to the first supply section Z1 between the pressure sensor P1 and the third mass flow controller F3.

[0072] In the illustration in FIG. 3, another embodiment is shown. Only the differences from the illustration in FIG. 1 are explained below.

[0073] The first supply section has a pressure controller PC1, wherein the pressure controller PC1 is arranged to be parallel to the third mass flow controller F3.

[0074] As a result, the first supply section has two line sections running parallel to one another, each with either the pressure controller PC1 or the mass flow controller F3.

[0075] During operation, either the third mass flow controller F3 or the pressure controller is always kept in an off state, which is to say, for example, the flow of the mass flow controller F3 is set to zero, so that the gas flow only moves through one of the two parallel line sections of the first supply section.

[0076] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.