Pseudomorphic Si1-x-yGexCy alloy layers on Si (100) with band-edge photoluminescence and without defect-related luminescence have been achieved. The photoluminescence was measured from 2 to 77 K and was used to make a direct measurement of the band gap shift as a function of strain reduction as C was added. Compared to the effect of just reducing Ge content, results show that as C is added, strain is reduced more efficiently than the band gap is increased. Furthermore, results imply that a fully strain-compensated Si1-x-yGexCy layer on Si (100) would have a band gap much less than that of Si, and suggest that initial C incorporation reduces the band gap of relaxed, unstrained Si 1-x-yGexCy alloys.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)