3C-SiC films have been deposited on Si （111） substrates by the low-pressure vertical chemical vapor deposition （LPVCVD） with gas mixtures of SiH4, Calls and H2. The growth mechanism of SiC films can be obtained th...3C-SiC films have been deposited on Si （111） substrates by the low-pressure vertical chemical vapor deposition （LPVCVD） with gas mixtures of SiH4, Calls and H2. The growth mechanism of SiC films can be obtained through the observations using field emission scanning electron microscope （FESEM）. It is found that the growth process varies from surface control to diffusion control when the deposition temperature increases from 1270 to 1350℃. The X-ray diffraction （XRD） patterns show that the SiC films have good crystallinity and strong preferred orientation.The results of the high resolution transmission electron microscopy （HRTEM） image and the transmission electron diffraction （TED） pattern indicate a peculiar superlattice structure of the film. The values of the binding energy in the high resolution X-ray photoelectron spectra （XPS） further confirm the formation of SiC.展开更多
The D0h luminescence of ZnO films deposited on p-type Si substrates is produced by metal-organic chemical vapor deposition(MOCVD).After annealing in the air at 700°C for an hour,the photoluminescence(PL)spectra,t...The D0h luminescence of ZnO films deposited on p-type Si substrates is produced by metal-organic chemical vapor deposition(MOCVD).After annealing in the air at 700°C for an hour,the photoluminescence(PL)spectra,the I-V characteristics and the deep level transient spectroscopy(DLTS)of the samples are measured.All the samples have a rectification characteristic.DLTS signals show two deep levels of E1 and E2.The Gaussian fit curves of the PL spectra at room temperature show three luminescence lines b,c and d,of which b is attributed to the exciton emission.The donor level E1 measured by DLTS and the location state donor ionization energy Ed of the closely neighboring emission lines c and d are correlated.E1 is judged as neutral donor bound to hole emission(D0h).Moreover,the intensity of the PL spectra decreases while the relative density of E2 increases,showing that E2 has the property of a nonradiative center.展开更多
基金Financial support from the National Natural Science Foundation of China under the grant No.50132040 is grate-fully acknowledged.
文摘3C-SiC films have been deposited on Si （111） substrates by the low-pressure vertical chemical vapor deposition （LPVCVD） with gas mixtures of SiH4, Calls and H2. The growth mechanism of SiC films can be obtained through the observations using field emission scanning electron microscope （FESEM）. It is found that the growth process varies from surface control to diffusion control when the deposition temperature increases from 1270 to 1350℃. The X-ray diffraction （XRD） patterns show that the SiC films have good crystallinity and strong preferred orientation.The results of the high resolution transmission electron microscopy （HRTEM） image and the transmission electron diffraction （TED） pattern indicate a peculiar superlattice structure of the film. The values of the binding energy in the high resolution X-ray photoelectron spectra （XPS） further confirm the formation of SiC.
基金supported by the National Natural Science Foundation of China (Grant Nos.50472009,10474091)the Knowledge Innovation Engineering of the Chinese Academy of Sciences (kjcx2-sw-04-02).
文摘The D0h luminescence of ZnO films deposited on p-type Si substrates is produced by metal-organic chemical vapor deposition(MOCVD).After annealing in the air at 700°C for an hour,the photoluminescence(PL)spectra,the I-V characteristics and the deep level transient spectroscopy(DLTS)of the samples are measured.All the samples have a rectification characteristic.DLTS signals show two deep levels of E1 and E2.The Gaussian fit curves of the PL spectra at room temperature show three luminescence lines b,c and d,of which b is attributed to the exciton emission.The donor level E1 measured by DLTS and the location state donor ionization energy Ed of the closely neighboring emission lines c and d are correlated.E1 is judged as neutral donor bound to hole emission(D0h).Moreover,the intensity of the PL spectra decreases while the relative density of E2 increases,showing that E2 has the property of a nonradiative center.
