Low-temperature silicon epitaxy by ultrahigh vacuum/chemical vapor deposition

We have successfully demonstrated the use of a novel chemical vapor deposition technique, ultrahigh vacuum/chemical vapor deposition, to deposit homoepitaxial silicon layers of high crystalline perfection at low temperatures (T≥750°C). Rutherford backscattering and transmission electron microscopy showed the transition to epitaxial silicon growth took place in the range 700-750°C, and secondary ion mass spectrometry showed typical oxygen and carbon levels to be near the detection limits of the technique 10 16-1017 cm-3. In addition, abrupt dopant transitions have been demonstrated, with B levels dropping four orders of magnitude, 1019-10 15 B/cm3, in the first 1000 angstroms of an intrinsic epilayer.