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Initial growth stage evaluation of high quality ZnSe films deposited on a glass substrate was investigated. The self-limiting monolayer epitaxial process was used to pregrowth the buffer layer for a zinc selenide (ZnSe) film deposited. After alternating depositions for several cycles, the growth mode was changed to the molecular beam deposition mode under growth conditions. Films deposited at substrate temperatures of 250–350 °C and Se/Zn beam equivalent pressure ratios of 0.77–1.87 were investigated. The crystal structure and the preferred orientation of as-grown ZnSe films were examined using x-ray diffraction patterns. The optical properties of the ZnSe films were revealed by photoluminescence spectra. The characteristics of the ZnSe films with and without a buffer layer were compared and discussed in detail. Finally, the results demonstrate how the quality of ZnSe film can be improved on glass substrates for application to various devices.

A simple digital measurement system of 2-detector Doppler broadening is presented. We use a data acquisition (DAQ) card to digitalize the pulse from main amplifier, and use software to process the digitalized pulse. We demonstrate that DAQ card with software can replace some conventional analog electronic instruments, such as gate generator, delay and coincidence system. The two-dimensional correlation spectrum shows that this system is as good as a conventional analog measurement system. The system is more convenient and more reliable because of using little analog hardware.

A new method of subtracting the chance coincidence background is presented. The two-dimensional (2D) background spectrum is discussed in detail. We found that the Compton scattering boundary is not parallel to the axis in the 2D spectrum. The conclusion has been demonstrated by some experiments.

The two-dimensional electron gas in δ-doped double quantum wells has been studied by using the Shubnikov–de Haas measurement. It was discovered that the δ-doping layer at the central barrier is able to prevent the electron coupling in the two wells and that the persistent photoconductivity can be reduced due to the thinner barrier. A δ-doped multiple quantum well structure for photodetector application was also proposed.