SiGe/Si quantum wells with abrupt interfaces grown by atmospheric pressure chemical vapor deposition

Atmospheric pressure chemical vapor deposition has been used to grow SiGe/Si quantum well structures on (001) oriented Si substrates. SiCl2H2 and GeH4 were used as reactive gases in a H2 atmosphere. The hydrogen ambient is shown to greatly facilitate the deposition of quantum wells with abrupt interfaces in the temperature range of 550-750 °C. The interface roughness is determined to be less than two monolayers, as shown by X-ray reflectivity, X-ray diffractometry data and the characteristics of resonant tunnel diodes showing a peak to valley ratio of 4.2. Photoluminescence spectra with resolved lines of no-phonon and phonon assisted recombination processes are observed. © 1995.