Image Number 3 for United States Patent #4743565.
Submicron lateral device structures, such as bipolar transistors, Schottky Barrier diodes and resistors, are made using self-aligned fabrication techniques and conventional photolithography. The devices are made using individual submicron silicon protrusions which extend outwardly from and are integral with a silicon pedestal therefor. Both PNP and NPN transistors may be made by diffusing appropriate dopant material into opposing vertical walls of a protrusion so as to form the emitter and collector regions. The protrusions themselves are formed by anisotropically etching the silicon using submicron insulating studs as a mask. The studs are formed using sidewall technology where a vertical sidewall section of as layer of insulating material is residual to a reactive ion etching process employed to remove the layer of insulating material.