Optimum Reduced Pressure Epitaxial Growth Process
Original Publication Date: 1985-Jan-01
Included in the Prior Art Database: 2005-Feb-18
Boron autodoping (p type) is reduced by the use of selectively changed arsine (or dopant) flow levels during reduced pressure epitaxial deposition upon substrates having localized subcollector and isolating areas. Epitaxial deposition pressure is maintained constant at about 80 Torr while the arsine flow level is increased during the initial 0.2 to 0.5 mm epitaxial growth to compensate for boron autodoping from P-doped isolation areas in the surface of the underlying substrate. The arsene level is lowered during subsequent epitaxial growth as determined by surface C0 only. Optimum arsine flows versus the ratio of subcollector to isolation areas of the substrate can be found by experiments directed at the optimization of leakage-limited yield and performance impacts.