Liquid phase epitaxial growth with interfacial temperature difference
AssigneeRCA Corporation
InventorsHarry Francis Lockwood, Michael Ettenberg
Life of this patent
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Abstract
A thin layer of semiconductor material with an extremely smooth surface can be grown on a substrate by liquid phase epitaxy. When the growing solution contacts the surface of the substrate, the substrate is at a lower temperature than the solution. The temperature difference should be less than 1.degree. C and depends upon the desired degree of smoothness. Both the substrate and the solution are then cooled to permit deposition of the layer.
Claims6
A method for growing a layer of crystalline semiconductor material by liquid phase epitaxy comprising the steps of:
- heating a charge composed of a semiconductor material and a solvent to melt the charge and form a solution of the semiconductor material in the solvent;
- heating a substrate to a lower temperature than the solution where the temperature difference is less than 1.degree. C;
- bringing the substrate into contact with the solution;
- cooling the solution and substrate at the same rate to deposit a layer of semiconductor material onto the substrate;
- and
- removing the substrate from contact with the solution after a predetermined interval.
A method for growing multiple layers of crystalline semiconductor material by liquid phase epitaxy, said method comprising the steps of:
- heating a plurality of charges each composed of semiconductor material and a solvent, to melt the charge and form a solution of the semiconductor material in the solvent, each successive solution being maintained at a higher temperature, the temperature difference being less than 1.degree. C;
- heating a substrate to a lower temperature than the lowest temperature of said solutions, the temperature difference being less than 1.degree. C;
- bringing the substrate successively into contact with each solution for a predetermined interval, commencing with the coolest and progressing to the hottest solution;
- and
- cooling the solutions and the substrate at the same rate while they are in contact to deposit layers of the semiconductor material onto the substrate.
Dependencies are inferred from the claim text.