Showing papers by "Youdou Zheng published in 1997"
TL;DR: In this paper, the effects of compressive and extensive strain on the atomic distribution have been studied by Raman scattering, and the effect can be suppressed by increasing the substrate temperature or increasing the Ge content in the Si-Ge alloy.
Abstract: The effects of compressive and extensive strain on the atomic distribution have been studied by Raman scattering. Compressive strain will make the atoms distribute inhomogeneously and nonuniformly. This effect can be suppressed by increasing the substrate temperature or increasing the Ge content in the Si-Ge alloy. The atoms are distributed uniformly and randomly in extensively strained Ge-Si alloys.
5 citations
TL;DR: In this paper, the SiGe/Ge heterojunction infrared detectors have been fabricated with Si1−xGex-Si heterostructures epitaxially grown on Ge substrates by rapid thermal process/very low pressure-chemical vapor deposition.
Abstract: Novel SiGe/Ge heterojunction infrared detectors have, for the first time, been fabricated with Si1−xGex–Si heterostructures epitaxially grown on Ge substrates by rapid thermal process/very low pressure-chemical vapor deposition. The peak value of the spectrum response ranges from 1.3 to 1.55 μm. The responsivity at 1.55 μm is higher than 0.7 A/W at zero bias. The dark current density is as low as 4×10−7 A/mm2 at −5 V.
2 citations
TL;DR: In this paper, the electrical and optical properties of double heterostructure blue light-emitting diodes, with In0.06Ga0.94N:Zn, Si active layer, at 77 and 300 K were studied.
Abstract: In this paper, we studied the electrical and optical characteristics of Nichia double heterostructure blue light-emitting diodes, with In0.06Ga0.94N:Zn, Si active layer, at 77 and 300 K. Measurement of the forward bias current-voltage behavior of the device demonstrates a departure from the Shockley model of p-n diodes, and it is observed that the dominant mechanism of carrier transport across the junction is associated with carrier tunneling. Electroluminescence experiments of the devices were performed. We obtained an emission peak located at 2.80 eV, and a relatively weaker short-wavelength peak of 3.2 eV. A significant blue shifts of the optical emission peak which is consistent with the tunneling character of electrical characteristics was observed. Furthermore, we studied the properties of electroluminescence under various pulsed currents, and a degradation in I-V characteristics and a low resistance ohmic short were observed.
1 citations
TL;DR: In this paper, the experiment results of wet oxidation of Si1-xGex on SiO2 were reported and a possible mechanism was proposed to explain the effect of the oxidation.
Abstract: In this paper, we report on the experiment results of wet oxidation of Si1-xGex on SiO2. AES and XPS measurements were performed to study the effect of the oxidation on the Si1-xGex layer. A possible mechanism was proposed.
TL;DR: In this paper, the growth rate of the GeSi alloy increases as the Si atoms are incorporated into the geSi alloy at a proper temperature and the high substrate temperature will cause the Si fraction and GeSi growth rate to increase.