LPE Semiconductor material transfer method

DETAILED DESCRIPTION The instant invention sets forth a method of growing patterned shapes on an unmasked surface of a seed semiconductor wafer or other planar semiconductor surfaces.
A technique which has come into use for making certain types of semiconductor devices, particularly semiconductor devices made of group III-V semiconductor materials and their alloys, such as light emitting devices and transferred electron devices is known as "liquid phase epitaxy.
" Liquid phase epitaxy (LPE) is a method for depositing an epitaxial layer of a single crystalline semiconductor material on a substrate wherein a surface of the substrate is brought into contact with a solution of a semiconductive material so that a portion of the semiconductor material in the solution precipitates and deposits on the substrate as an epitaxial layer, and the remainder of the solution is removed from the substrate.
The solution may also contain a conductivity modifier which deposits with the semiconductor material to provide an epitaxial layer of desired conductivity type.
Two or more epitaxial layers can be deposited one on top of the other to form a semiconductor device of a desired construction including a semiconductor device having a PN junction between adjacent epitaxial layers of opposite conductivity type.
This method is carried out with a conventional furnace boat and slide.
Into one bin of the boat is placed a liquid growth solution having elemental constituents the same as the first wafer in the slide.
The percentage of each constituent is determined so that the liquid growth solution when placed in contact with the first wafer in the slide results in none of the wafer material being dissolved at a predetermined equilibrium temperature.
The first wafer in the slide has a patterned surface protected by, for example, silicon dioxide with openings therein producing exposed areas.
Conventional photolithographic techniques are used to mask and to create exposed areas on the surface of the first wafer.
A second wafer being a seed wafer following the first wafer in the slide has a totally exposed surface onto which structures are to be grown