Si Contamination in Epitaxial Boron Monophosphide

Ion microanalysis has been applied to the BP single-crystal layers grown on Si substrates in a BCl₃-PCl₃-H₂ system. At the interface there is a large Si Profile of exponential form, which is mainly due to autodoping from the substrate. Furthermore, considerable contamination is observed all over the crystal, whose source is the heated portion of the quartz system. Both effects are affected by the growth conditions and are seen to diminish with decreasing growth rate. The dependence on the orientation is also discussed. A correlation with carrier concentration proves that Si atoms act as donors in BP.