摘要:

We present both theoretical and experimental results in silicon which clearly demonstrate that at time scales of 20 to 40 ps, after the pump laser pulse and at fluences greater than 100 mJ/cm2, the carrier density of the electron‐hole plasma drops for increasing fluence; this is not explained by Auger recombination. We show that this drop is specific to plasmon‐phonon‐assisted recombination, which naturally explains this behavior.

ISSN:0003-6951    

DOI:10.1063/1.98942

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

HgCdTe infrared photovoltaic detectors were fabricated on silicon substrates for the first time by using intermediate CdTe and GaAs epitaxial layers. No cracking or degradation was observed after thermal cycling these devices (cutoff wavelength of 5.5 &mgr;m andR0Aas high as 200 &OHgr; cm2at 80 K). Secondary ion mass spectrometry and Auger data substantiate that a CdTe buffer layer can prevent Ga diffusion from the intermediate GaAs epitaxial layer from inadvertently converting thep‐HgCdTe ton‐type at growth temperatures as high as 500 °C.

ISSN:0003-6951    

DOI:10.1063/1.98943

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

The apparatus and its preliminary results of gas source silicon molecular beam epitaxy are reported for the first time. In this study, silane (SiH4) was used as a source gas. A subchamber was designed to control the gas flow precisely. SiH4exposure during the initial cleaning was effective in lowering the cleaning temperature and saving the cleaning time. Epitaxial silicon films grew uniformly on 4‐in. wafers. There was no spitting defect on the epitaxial films. Moreover, selective epitaxial growth was realized using a patterned SiO2mask.

ISSN:0003-6951    

DOI:10.1063/1.99009

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

We report, in this letter, the successful growth of Ga0.5In0.5As/InP heterostructures by alternating the growth ofn(GaAs) andn(InAs) atomic layers. Such structures are designed as (GaAs)n(InAs)n. The influence of parameters such asnor the introduction of a purging time between the InAs‐GaAs monolayers has been investigated. Low‐temperature photoluminescence experiments showed that (GaAs)n(InAs)n/InP multiquantum wells had a better uniformity in composition and thickness than the conventional Ga0.5In0.5As/InP system.

ISSN:0003-6951    

DOI:10.1063/1.98944

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

We report the high‐power operation of &lgr;=1.3 &mgr;m InGaAsP double‐channel planar buried‐heterostructure lasers with asymmetric mirror coatings. A stack of four dielectric layers is used to raise the reflectivity of one facet to over 80%, and the thickness of a single layer coating on the output facet is chosen to reduce the reflectivity to about 4%. The resulting lasers are characterized by a low threshold current of 25 mA, slope efficiency as high as 50%, and a power output of as much as 150 mW (at 5 °C) at a current of less than 300 mA. The lasers operate in a single transverse mode over the entire current range and as much as 45 mW of power could be coupled into a lensed single‐mode fiber. Preliminary high‐power aging data show excellent device reliability.

ISSN:0003-6951    

DOI:10.1063/1.98945

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

We have discovered conditions for the selective lift‐off of large area epitaxial AlxGa1−xAs films from the substrate wafers on which they were grown. A 500‐A˚‐thick AlAs release layer is selectivity etched away, leaving behind a high‐quality epilayer and a reusable GaAs substrate. We have measured a selectivity of ≳107between the release layer and Al0.4Ga0.6As. This process relies upon the creation of a favorable geometry for the outdiffusion of dissolved H2gas from the etching zone.

ISSN:0003-6951    

DOI:10.1063/1.98946

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Reactive ion etching is important for III‐V device fabrication. Commonly encountered applications include the need to remove an epitaxial layer selectively from underlying layers and the need for definition of mesas and other structures with carefully controlled dimensions. We present results showing the use of very thin Al0.9Ga0.1As and In0.2Ga0.8As stop‐etch layers, which when used in conjunction with a particular etch chemistry can provide highly selective removal of epitaxial layers in GaAs‐based III‐V compound semiconductors. In addition, we report the selective removal of an Al0.3Ga0.7As layer from underlying GaAs by the use of a thin In0.2Ga0.8As interlayer.

ISSN:0003-6951    

DOI:10.1063/1.98947

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

A novel, band‐inverted semiconductor junction is proposed. The heterojunction consists of two column V semimetals that have undergone a semimetal‐semiconductor transition, i.e., a thin Bi film of thickness ∼100 A˚ and a Bi1−xSbxalloy with 0.06<x<0.3. Such a junction will support the recently predicted interfacial states. Results of calculations on the dispersion relation and optical transitions pertaining to the interfacial states are presented. It is shown that the optical transition rate between an interfacial state and the conduction state is comparable to that of a conduction‐valence band transition. It is also shown that the optical transitions have very interesting polarization dependences.

ISSN:0003-6951    

DOI:10.1063/1.98948

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

Current‐voltage behavior is studied experimentally in a Hg0.78Cd0.22Te‐CdTe‐Hg0.78Cd0.22Te heterostructure grown by molecular beam epitaxy. At temperatures above 160 K, energy‐band diagrams suggest that the dominant low‐bias current is thermionic hole emission across the CdTe barrier layer. This interpretation yields a direct determination of 390±75 meV for the HgTe‐CdTe valence‐band discontinuity at 300 K. Similar analyses of current‐voltage data taken at 190–300 K suggest that the valence‐band offset decreases at low temperatures in this heterojunction.

ISSN:0003-6951    

DOI:10.1063/1.98949

出版商:AIP    

年代:1987

数据来源: AIP

摘要:

High electron mobility transistors are sensitive to light since illumination ionizes deep donor centers and increases the drain current. In this letter the first observation of negative photoconductivity, i.e., drain current decreasing with light, will be reported. The current‐voltage characteristics were enhanced by shining white light onto the devices showing negative photoconductivity.

ISSN:0003-6951    

DOI:10.1063/1.98950

出版商:AIP    

年代:1987

数据来源: AIP