GAS-PHASE CONTRIBUTION TO CARBON INCORPORATION AND EXTRACTION MECHANISMS FOR LEC GAAS

The H2 and CO concentrations in the atmosphere inside an LEC puller have been found to vary widely according to several melt preparation condition, such as in-situ melt purification, water content of the B2O3 encapsulant, the quartz cap attachment on the crucible, as well as with the progress in the pulling process. Results obtained from measurements of the carbon content of the crystals and from gas analysis in the puller have led to the conclusion that H2 and CO in the atmosphere play significant roles in carbon incorporation and extraction for LEC GaAs single crystals. © 1990, Elsevier Science Publishers B.V.. All rights reserved.