US 4,732,110 AGranted

Inverted positive vertical flow chemical vapor deposition reactor chamber

AssigneeHughes Aircraft Company

InventorJames D. Parsons

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Abstract

A chemical vapor deposition (CVD) reactor system is described comprising a substantially vertical reactor tube having a gas inlet and a gas outlet, a pedestal mounted within the reactor tube having a structure for securing a substrate thereto so that a surface of the substrate is exposed downward, and apparatus for providing a gas mixture to the reactor tube, the gas mixture being introduced into the reactor tube via the gas inlet and subsequently withdrawn via the gas outlet, the gas inlet and outlet being positioned, with respect to the substrate, below and above, respectively. The gas mixture is maintained in substantially uniform plug flow as it is directed into close proximity to the exposed surface of the substrate. This permits the CVD growth of physically uniform layers, both in terms of thickness and composition, having low contamination concentrations over large substrate surface areas.

Claims16

Dependent claims

A chemical vapor deposition (CVD) reactor system comprising a vertical reactor chamber, a source of a reactant gas compound having a deposition component as a fraction thereof, means for introducing said reactant gas compound into said reactor chamber, and a substrate having a major surface suitable for receiving said deposition component, wherein said reactor chamber comprises:

(a) a pedestal having
means for securing said substrate to said pedestal such that said major surface is exposed facing downward and having means above said substrate for removing any residual amounts of said reactant gas components and any residual decomposition reactant products;
(b) means for heating said substrate to a temperature sufficient to induce the decomposition of said compound when provided in close proximity with the exposed surface of said substrate;
(c) said reactor chamber being constructured so as to induce a vertical upward plug flow of said compound introduced into said reactor chamber to be positively directed into close proximity with the exposed surface of said substrate, so that said decomposition component is positively directed onto the exposed major surface of said substrate.

1 more element

A chemical vapor deposition reactor system comprising:

(a) a reactor tube cap having a gas outlet;
and
(b) a reactor tube having:
(i) an upper portion connected to said cap, the inner surface of said upper tube portion defining a substantially uniform cylindrical volume and having a substantially vertical axis, and
(ii) a lower tube portion, contiguous with said upper tube portion, and including a gas inlet, the inner surface of said lower tube portion defining a uniform funnel shaped volume and providing a smooth transition from said gas inlet to said upper tube portion, said gas inlet being positioned at the vertex of said lower tube portion such that gas introduced at said gas inlet forms a substantially uniform plug flow within said lower tube portion;
(c) means for supporting a substrate for growing a single crystal on a major surface thereof, wherein said support means include means for supporting the major surface of the substrate in a downward facing position, said support means positioned in said upper portion of said reactor tube (1) such that gas enters said upper portion below the substrate and exits above the substrate and (2) such that the substrate is substantially symmetrically centered about and substantially perpendicular to the cylindrical axis of said upper tube portion;
(d) means for heating a substrate;
on the support means.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 07/045,258Filed 20 Apr 1987 · continuation
Priority: 29 Apr 1983
Granted: 22 Mar 1988
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

C23C 16/45582
Characterised by the method used for introducing gases into reaction chamber or for modifying gas flows in reaction chamber: expansion of gas…
C30B 25/08
Epitaxial-layer growth: reaction chambers; Selection of materials therefor
C30B 25/14
Epitaxial-layer growth: feed and outlet means for the gases; Modifying the flow of the reactive gases
C23C
Coating metallic material