Eliminating Boron and Arsenic Autodoping Through Reduced Pressure
Original Publication Date: 1981-Aug-01
Included in the Prior Art Database: 2005-Feb-12
Autodoping of boron (B) or arsenic (As) occurs inside epitaxial layers as a result of the incorporation of impurity atoms from buried layer structures. It is well known that As autodoping is significantly reduced by using a reduced pressure epitaxial deposition process. However, very little is known about the behavior of B. A significant amount of B autodoping has been found in silicon epitaxial films when deposited under reduced pressure conditions at 1150 Degrees C. Two-micron thick n type films, having 0.3-0.6 Omega cm resistivity (Rho), have been grown at a constant growth rate and at various pressures ranging from 80-760 torr. Lateral autodoping of B and As has been investigated as a function of the autodoping source area.