Hot Electron Ge/Si Lasers

Abstract : There are two major parts in this report. The first part concentrates on the photoluminescence studies of SiGe layers grown on Si. The second part reports on the investigation of novel nonvolatile random access memory devices. For the first part multiple exciton complexes confined in potential wells produced by alloy fluctuations are identified. It is found that the size of exciton complex is critically dependent of the size of potential well. The blue-shift of an optical transition line(D1) associated with dislocations is observed and correlated with Si-Ge interatomic diffusion at partial dislocation cores. For the second part, it is unambiguously determined that the band alignment is type II at the interface of ZnCdSe and InP. Negative differential resistance is observed in a single heterointerface well barrier structure with a current peak-to-valley ratio of 30 at room temperature. A bi resistance device using ZnCdMgSe/InP heterostructure was designed and demonstrated. A novel architecture is proposed for nonvolatile electrical random access memory based on the demonstrated bi-resistance device.