BAND ALIGNMENT IN SI1-YCY SI(001) AND SI1-XGEX/SI1-YCY/SI(001) QUANTUM-WELLS BY PHOTOLUMINESCENCE UNDER APPLIED [100] AND [110] UNIAXIAL-STRESS/

We use a novel wafer bending technique to study band alignment under a pplied uniaxial stress in Si1-yCy/Si and Si1-xGex/Si(1-y)Cy/Si heteros tructures. We confirm a type I alignment for Si1-yCy/Si and report the first observation of an elastic strain induced type I to type II tran sition in Si1-yCy/Si quantum wells. Results for a Si0.84Ge0.16/Si0.99C 0.01/Si structure support a type IT transition between the SiGe valenc e band and the SiC conduction band. These results also indicate a cond uction band offset of at most 65% of the band gap difference for Si1-y Cy/Si with y=0.5% or 1%.