摘要:

A low threshold buried heterostructure laser, a metal‐semiconductor field‐effect transistor, and ap‐i‐nphotodiode have been integrated on a semi‐insulating GaAs substrate. The circuit was operated as a rudimentary optical repeater. The gain bandwidth product of the repeater was measured to be 178 MHz.

ISSN:0003-6951    

DOI:10.1063/1.94598

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

We report measurements of the temperature dependence of the threshold current of GaAs, 1.3‐&mgr;m InGaAsP, and 1.5‐&mgr;m InGaAsP double heterostructure lasers using short electrical pulses.T0∼200 K is observed for all the lasers. These highT0values show that the carrier density at threshold does not increase rapidly with increasing temperature in any of the lasers studied and thus the observed low cwT0of InGaAsP lasers is primarily due to a decrease of the carrier lifetime at threshold with increasing temperature.

ISSN:0003-6951    

DOI:10.1063/1.94605

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The mass‐transport technique has been used to improve chemically etched mirrors on GaInAsP/InP double heterostructure wafers. Vertical and flat mirror facets have been obtained. Buried‐heterostructure lasers fabricated with one such mirror and the other mirror cleaved show high device yield with threshold currents as low as 6 mA and differential quantum efficiency as high as 33%.

ISSN:0003-6951    

DOI:10.1063/1.94606

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The photorefractive effect has been observed for the first time in semi‐insulating InPe:Fe and GaAsCr. These materials are sensitive and versatile recording media for high bit rate parallel optical processing in the 0.8–1.8‐&mgr;m spectral region using injection lasers of milliwatt power levels.

ISSN:0003-6951    

DOI:10.1063/1.94607

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

InP and In‐oxide films have been deposited on quartz, GaAs, and InP substrates by excimer laser induced photodecomposition of (CH3)3InP(CH3)3and P(CH3)3vapors at 193 nm. The oxide film refractive index and stoichiometry are close to In2O3. Phosphorus incorporation in the films was greatly enhanced by focusing the laser beam to promote multiple‐photon dissociation processes. These conditions also lead to enhanced carbon inclusion in the films, due to formation of species such as CH and CH2in the gas phase. However, this carbon inclusion could be suppressed by focusing the beam onto the surface at normal incidence. In the irradiated zone InP could be deposited with P(CH3)3‐to‐(CH3)3InP(CH3)3ratios of only ∼1:1. The technique offers several potential advantages over conventional metalorganic chemical vapor deposition, including lower temperature, enhanced rates, safer gases, and three‐dimensional film composition control. Strong atomic In emission is observed in the gas phase above the depositing film, due to a multiple photon dissociation process. Gas phase fluorescence from P, CH, and C was also observed. These emissions give insight into the photodecomposition mechanism and also serve as a monitor of metalorganic precursor concentrations.

ISSN:0003-6951    

DOI:10.1063/1.94608

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

Ultrasonic transducer arrays suffer from the effects of acoustic cross coupling. The beam pattern and temporal response are degraded. The mechanism for acoustic cross coupling has been postulated to be surface wave propagation along the array. Our theory has shown that surface waves are indeed responsible, and that they may propagate in either the backing or load medium. The new theory is based on an extension to periodic systems of the theory for excitation of a uniform semi‐infinite substrate by a single line source. It provides a quantitative model for cross coupling, as well as physical insight into its mechanism.

ISSN:0003-6951    

DOI:10.1063/1.94609

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

A simple analysis of the neutralization of an intense ion beam propagating in vacuum is presented which predicts the principal results of previous numerical simulation and experiments.

ISSN:0003-6951    

DOI:10.1063/1.94597

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

Morphological variations of graphite strip heater recrystallized silicon‐on‐insulator formed in the initial stage of seeded growth have been analyzed to examine the thermal gradient effect upon the growth stability. Systematic transition of the stable growth into an orderly breakdown of faceted, cellular, and dendritic configurations has been attributed to the decreasing temperature gradient in this region. There are indications that constitutional supercooling could be responsible for the interface stability breakdown and that increased thermal gradients can suppress the onset of breakdown and maintain the stable growth over an extended distance.

ISSN:0003-6951    

DOI:10.1063/1.94610

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

Crystallographic orientation control using a new double laser annealing of silicon stripes in SiO2grooves is presented. In the laser recrystallization of silicon stripes in the structure consisting of SiO2grooves/polysilicon sublayer/quartz glass substrates, first, a part of the Si stripe is intentionally recrystallized by a cw Nd:yttrium aluminum garnet laser to obtain ⟨100⟩ texture with a small grain size. Next, using these ⟨100⟩ oriented Si grains as seed crystals, ⟨100⟩ oriented large Si stripes are obtained by scanning a cw Ar ion laser along the stripe direction. This double laser annealing technique for orientation control can potentially be used to fabricate three‐dimensional devices.

ISSN:0003-6951    

DOI:10.1063/1.94611

出版商:AIP    

年代:1984

数据来源: AIP

摘要:

The effects of mercury and krypton on the glow discharge decomposition of disilane have been studied. It is found that mercury‐sensitized plasma decomposition of disilane yields higher deposition rate hydrogenated amorphous silicon (a‐Si:H) films. At a deposition rate as high as 60 A˚/s no change was observed on the dark and photoconductivities. A similar effect was obtained in krypton‐sensitized plasma decomposition of disilane.

ISSN:0003-6951    

DOI:10.1063/1.94612

出版商:AIP    

年代:1984

数据来源: AIP