摘要:

The surface of monocrystalline silicon was chemically converted with hydrocarbon to polycrystalline &bgr;‐silicon carbide, and the growth mechanism was investigated by means of14C tracer method. It is shown that the growth of the silicon carbide layer is due to diffusion of silicon through the SiC layer so that the Si&sngbnd;SiC conversion is taking place at the surface of the sample. Dependence of layer thickness on carbidizing time and on hydrocarbon concentration in the carrier gas hydrogen was measured.

ISSN:0003-6951    

DOI:10.1063/1.1654282

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

The intrinsic response time &tgr;iof semiconductor avalanches has been determined from microwave measurements on Si, Ge, and GaAs IMPATT diodes of various structures (n+‐p, p+‐n, Schottky barrier). A theory has been developed to calculate &tgr;ifor these diodes. It was found that the effect of carrier diffusion has to be taken into account to remove a systematic discrepancy between experimental and theoretical values of &tgr;i. For Si the value of the average high‐field diffusion constantD¯=80 cm2/sec forE=400 kV/cm, taken from the literature, could be used satisfactorily. For Ge and GaAs, where no information onD¯is available,D¯=100 cm2/sec forE=200 kV/cm andD¯=250 cm2/sec forE=400 kV/cm, respectively, had to be chosen to explain the experimental values of &tgr;i.

ISSN:0003-6951    

DOI:10.1063/1.1654283

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

Fabrication of a circular strip waveguide by ion implantation of fused silica through a mask made by electron‐beam exposure of polymethylmethacrylate (PMMA) is described. This technique has an advantage in its simplicity and the small number of processing steps involved. Guidance of 0.6328‐&mgr;m light from a He&sngbnd;Ne laser through the guide is demonstrated.

ISSN:0003-6951    

DOI:10.1063/1.1654284

出版商:AIP    

年代:1972

数据来源: AIP

摘要:

An acoustic modulator using a liquid crystal and a piezoelectric driver is described. The response time of the modulator is less than the time needed for the onset of mechanical stress. Actually it is governed only by the electromechanical properties of the piezoelectric driver used.

ISSN:0003-6951    

DOI:10.1063/1.1654285

出版商:AIP    

年代:1972

数据来源: AIP

ISSN:0003-6951    

DOI:10.1063/1.1654286

出版商:AIP    

年代:1972

数据来源: AIP