Abstract: An apparatus for automatically measuring the depth and rate of etching of a semiconductor body (10) comprises an interferometer (18) and a counter circuit (28). The interferometer (18) directs light towards the semiconductor body (10) and detects the intensity of the light reflected therefrom which varies periodically during etching. The counter circuit (28) is responsive to the periodically varying intensity of the reflected light and automatically determines the number of cycles and the frequency thereof to compute the etch depth and etch rate therefrom.

Abstract: A chemical vapor deposition epitaxial reactor (10) comprised of a quartz tube (12) with banks of IR lamp proximate the outside surface thereof. A splitter plate (30) located at the inlet of the tube (12) separates reactive gases and nonreactive gases directed longitudinally into the tube. The nonreactive gases, directed along the inside surface of the tube (12), substantially prevents unwanted reactant deposition on the inside surface of the tube (12).

Abstract: A chemical vapor deposition epitaxial reactor (10) comprised of a quartz tube (12) with banks of IR lamp proximate the outside surface thereof. A splitter plate (30) located at the inlet of the tube (12) separates reactive gases and nonreactive gases directed longitudinally into the tube. The nonreactive gases, directed along the inside surface of the tube (12), substantially prevents unwanted reactant deposition on the inside surface of the tube (12).

Abstract: A method for determining the optimum time at which a plasma etching operation should be terminated. The optical emission intensity (S.sub.1) of the plasma in a narrow band centered about a predetermined spectral line, indicative of the gas phase concentration of a plasma etch product or reactant species. The optical emission intensity (S.sub.2) of the plasma in a wide band centered about the predetermined spectral line, indicative of a background emission signal is also monitored. The intensity (S.sub.1L) of the spectral line is then determined in accordance with the equation S.sub.1L =S.sub.1 -k (.alpha.S.sub.2 -S.sub.1). The etching process is terminated when the monitored signal intensity (S.sub.1L) or its time derivative reaches a predetermined value.