The Si epitaxial films are grown on Si (100) substrates using pure Si2H6 as a gas source using ultrahigh vacuum chemical vapour deposition technology. The values of growth temperature Tg are 650 ℃, 700 ℃, 730 ℃, ...The Si epitaxial films are grown on Si (100) substrates using pure Si2H6 as a gas source using ultrahigh vacuum chemical vapour deposition technology. The values of growth temperature Tg are 650 ℃, 700 ℃, 730 ℃, 750 ℃, and 800 ℃. Growth mode changes from island mode to step-flow mode with Tg increasing from 650 ℃ to 700℃. Rippled surface morphologies are observed at Tg = 700 ℃, 730 ℃, and 800℃, but disappear when Tg = 750℃. A model is presented to explain the formation and the disappearance of the ripples by considering the stability of the step-flow growth.展开更多
Strain-compensated Ge/Si0.15Ge0.85 multiple quantum wells were grown on an Si0.1 Ge0.9 virtual substrate using ultrahigh vacuum chemical vapor deposition technology on an n+-Si(001) substrate. Photoluminescence mea...Strain-compensated Ge/Si0.15Ge0.85 multiple quantum wells were grown on an Si0.1 Ge0.9 virtual substrate using ultrahigh vacuum chemical vapor deposition technology on an n+-Si(001) substrate. Photoluminescence measurements were performed at room temperature, and the quantum confinement effect of the direct-bandgap transitions of a Ge quantum well was observed, which is in good agreement with the calculated results. The luminescence mechanism was discussed by recombination rate analysis and the temperature dependence of the luminescence spectrum.展开更多
Ge-on-Si p-i-n diodes are fabricated by using two-step Ge film epitaxial technology on Si substrates.A remarkable Franz-Keldysh effect is observed in the wavelength range of 1620-1640nm with a largestΔα/αof 2.8 at ...Ge-on-Si p-i-n diodes are fabricated by using two-step Ge film epitaxial technology on Si substrates.A remarkable Franz-Keldysh effect is observed in the wavelength range of 1620-1640nm with a largestΔα/αof 2.8 at 1640nm by optical responsivity measurement.The remarkable change of absorption coefficient in the considerable large wavelength range makes Ge-on-silicon a promising candidate for Si-based electro-absorption modulators.The initial design predicts a modulator of bandwidth~50 GHz,and the extinction ratio>7dB by the measured parameter.展开更多
基金supported by the Major State Basic Research Program of China (Grant No. 2007CB613404)the National High Technology Research and Development Program of China (Grant No. 2006AA03Z415)+1 种基金the National Natural Science Foundation of China(Grant Nos. 60676005,61036003,and 60906035)the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No. ISCAS2009T01)
文摘The Si epitaxial films are grown on Si (100) substrates using pure Si2H6 as a gas source using ultrahigh vacuum chemical vapour deposition technology. The values of growth temperature Tg are 650 ℃, 700 ℃, 730 ℃, 750 ℃, and 800 ℃. Growth mode changes from island mode to step-flow mode with Tg increasing from 650 ℃ to 700℃. Rippled surface morphologies are observed at Tg = 700 ℃, 730 ℃, and 800℃, but disappear when Tg = 750℃. A model is presented to explain the formation and the disappearance of the ripples by considering the stability of the step-flow growth.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61036003,61176013,61177038,and 60906035)the High Technology Research and Development Program of China(Grant No.2011AA010302)
文摘Strain-compensated Ge/Si0.15Ge0.85 multiple quantum wells were grown on an Si0.1 Ge0.9 virtual substrate using ultrahigh vacuum chemical vapor deposition technology on an n+-Si(001) substrate. Photoluminescence measurements were performed at room temperature, and the quantum confinement effect of the direct-bandgap transitions of a Ge quantum well was observed, which is in good agreement with the calculated results. The luminescence mechanism was discussed by recombination rate analysis and the temperature dependence of the luminescence spectrum.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61036003,61176013,60906035and 61177038,the National High-Technology and Research Development Program of China under Grant No 2011AA010302the Tsinghua National Laboratory for Information Science and Technology(TNList)Cross-discipline Foundation.
文摘Ge-on-Si p-i-n diodes are fabricated by using two-step Ge film epitaxial technology on Si substrates.A remarkable Franz-Keldysh effect is observed in the wavelength range of 1620-1640nm with a largestΔα/αof 2.8 at 1640nm by optical responsivity measurement.The remarkable change of absorption coefficient in the considerable large wavelength range makes Ge-on-silicon a promising candidate for Si-based electro-absorption modulators.The initial design predicts a modulator of bandwidth~50 GHz,and the extinction ratio>7dB by the measured parameter.