Abstract A reactor for depositing a thin layer of material on a semiconductor slice by thermal decomposition of reactant gases is disclosed which has a circular rail, a number of disk-shaped graphite susceptors or supports each having a flat face from which projects a circular retaining rim, a member rotating on an axis extending through the circular rail for rolling the susceptors along the rail while supporting the susceptors at an inclined angle, and an RF coil for heating the susceptors as they are rolled along the rail. The edge of a semiconductor slice placed on the face of the susceptor rolls around the rim of the susceptor as the susceptor rolls. This mechanism is enclosed in a chamber and the reactant gases passed through the chamber. Thus, anomalies in the RF field are compensated as the susceptor rolls around the rail to evenly heat the susceptor, thermal anomalies in the susceptors are compensated as the slice continually moves over the susceptor, and anomalies in the composition of the reactant stream are compensated as each semiconductor slice rotates about its own axis while being translated in a circular path through the vapor stream. Layers uniform in thickness within + OR - 0.5 percent have been achieved, representing an order of magnitude improvement over prior art devices, with corresponding improvements in the uniformity of doping levels and resistivities.
The combination of claim 1 wherein the reactant gas stream is made to flow downwardly over the substrates.
Claim 2
Dependent Claim
135 words
A vapor deposition coating system comprising in combination: a coating chamber; a plurality of disk-shaped support members within said chamber, each having a continuous rim on the outer face thereof to define a closed-bottom recess for holding a substrate to be coated; a disk-shaped substrate of a lesser diameter than, and supported within, the circular recess deFined by each said rim; means for rotating each of said support members at an inclined angle; means for orbiting said support members about a generally central point within said chamber and simultaneously with rotation induced by said means for rotating whereby to effect rolling movement of each said substrate relative to the rim associated therewith; means for heating said support members; and means for passing a reactive gas stream over and in contact with the substrates supported thereon.
Claim 3
Dependent Claim
22 words
A system as defined by claim 3 further including means for loading and unloading said support members into and from said chamber.
Claim 4
Dependent Claim
27 words
A system as defined by claim 3 wherein at least one of said support members has a plurality of recessed surfaces for holding a plurality of substrates.
Claim 5
Dependent Claim
22 words
A system as defined by claim 3 wherein said support members are graphite susceptors and said heating means comprises an RF coil.