STRAIN-INDUCED LATERAL BAND-GAP MODULATION IN SI1-XGEX SI QUANTUM-WELL AND QUANTUM-WIRE STRUCTURES/

We demonstrate two methods to induce lateral band gap modulation in bu ried Si1-xGex/Si quantum well structures (QWs). The basic feature of t he first one is to utilize the generation of inhomogeneous strain fiel d due to two-dimensional to three-dimensional growth mode transition o f SiGe/Si heterostructures in gas-source molecular beam epitaxy. The s econd one is to grow SiGe/Si QWs directly on artificially-v-grooved Si substrates. The both were found to be useful for inducing lateral ban d gap modulation as evidenced by photoluminescence spectroscopy.