摘要:

The very early stage of the thermal oxidation of single‐crystal Si has been the subject of continual study for the last two decades. In the light of very recent experimental oxidation data on the initial regime, we report that a simple thermionic electron flux from Si into SiO2closely agrees with the SiO2film growth rate. The importance of electrons for the oxidation kinetics has also been attested to in several recent experimental studies. Thus a consistent model is presented for the initial oxidation regime based on the electron flux as the rate limiting step.

ISSN:0003-6951    

DOI:10.1063/1.98861

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Measurements of Franz–Keldysh (FK) effects in GaAs‐AlxGa1−xAs heterostructures by variable angle of incidence spectroscopic ellipsometry are reported. The measured FK effects are due to the built‐in band bending at the surface and heterointerfaces, with no externally applied bias or modulating voltage. The polarity of the FK line shape indicates whether the field is uniform or nonuniform (inhomogeneous) in the direction along the growth axis, while the linewidth is determined by the peak field strength. This information can be used to characterize the doping concentration in the AlxGa1−xAs layer.

ISSN:0003-6951    

DOI:10.1063/1.98862

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

The defect properties of buried oxide silicon‐on‐insulator (SOI) formed by high dose O+ion implantation and annealed in the temperature range of 1150–1300 °C were examined using photoluminescence (PL) spectroscopy and transmission electron microscopy. The intensity of radiative defect levels at 0.814 and 0.862 eV measured by PL at 4.2 K was observed to decrease with increasing post‐implantation annealing temperature. A direct correlation between the radiative defect band intensities and etch defect density in the top silicon layer was observed. The correlation between defect density and PL defect band intensity was further verified by cross‐sectional transmission electron microscopy of the top silicon. This letter demonstrates for the first time the correlation between PL defect properties and microstructure of buried oxide SOI. From comparisons with radiative defect centers in oxygen precipitated and plastically deformed silicon, the radiative defect states in SOI silicon are shown to result from residual dislocations in the top silicon layer of the SOI structure.

ISSN:0003-6951    

DOI:10.1063/1.98863

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

The minority‐carrier mobility of electrons in metalorganic chemical vapor deposition grownp‐GaAs has been measured by a diffusion time‐of‐flight technique. Doping levels of 1×1017and 2×1018cm−3were investigated. The measured mobilities were about 2900 and 1300 cm2/V s, respectively. The minority‐carrier mobilities are lower than the expected majority‐carrier mobilities at the same doping levels. The lower mobility is caused by heavy‐hole scattering.

ISSN:0003-6951    

DOI:10.1063/1.98864

出版商:AIP    

年代:1987

数据来源: AIP