简介：TheeffectsofgrowthtimeonthestructureandmorphologyofcubicGaNnucleationlayersonGaAs(001)substratesbymetalorganicchemicalvapordeposition(MOCVD)havebeeninvestigatedusingasynchrotronX-raydiffraction(XRD).TheXRDresultsshowthattheGaN111reflectionsat54.75°inχareameasurablecomponent,howeverthe002reflectionsparalleltoGaAs(001)surfacearenotdetected.TheXRDΦscansandpolefiguresgiveaconvincingproofthattheGaNnucleationlatyersshowexactlythecubicsymmetricalstructure.Thecoherencelengthsalongtheclose-packed<111>directionestuimatedfromthe111peakarenanometerorderofmagnitude,Theoptimalphotoluminescence(PL)spectrumwasobtainedfromthecubicGaNepilayerdepositedonthenucleationlayerfor60sec.

简介：AseriesofGaAs/AlAsmultiple-quantumwellsdopedwithBeisgrownbymolecularbeamepitaxy.Thephotoluminescencespectraaremeasuredat4,20,40,80,120,and200K,respectively.Therecombinationtransitionemissionofheavy-holeandlight-holefreeexcitonsisclearlyobservedandthetransitionenergiesaremeasuredwithdifferentquantumwellwidths.Inaddition,atheoreticalmodelofexcitonicstatesinthequantumwellsisused,inwhichthesymmetryofthecomponentoftheexcitonwavefunctionrepresentingtherelativemotionisallowedtovarybetweenthetwo-andthreedimensionallimits.Then,withintheeffectivemassandenvelopefunctionapproximation,therecombinationtransitionenergiesoftheheavy-andlight-holeexcitonsinGaAs/AlAsmultiple-quantumwellsarecalculatedeachasafunctionofquantumwellwidthbytheshootingmethodandvariationalprinciplewithtwovariationalparameters.Theresultsshowthattheexcitonsareneither2Dnor3Dlike,butareinbetweenincharacterandthatthetheoreticalcalculationisingoodagreementwiththeexperimentalresults.

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简介：在测试了ＡｌＧａＡｓ／ＧａＡｓＨＢＴ（异质结晶体管）的直流特性和Ｓ参数的基础上，建立了其微波小信号等效电路，准确的等效电路有利于其微波线性应用的分析．应用Ｖｏｌｔｅｒａ级数，计算了ＡｌＧａＡｓ／ＧａＡｓＨＢＴ放大器的三阶互调失真，计算结果和双音测试结果相当一致，该ＨＢＴ良好的线性特性证明了其较好的线性应用前景

简介：High-strainInGaAs/GaAsquantumwells(QWs)aregrownbylow-pressuremetal-organicchemicalvapordeposition(LP-MOCVD).Photoluminescence(PL)atroomtemperatureisappliedforevaluationoftheopticalproperty.Theinfluenceofgrowthtemperature,V/IIIratio,andgrowthrateonPLcharacteristicareinvestigated.ItisfoundthatthegrowthtemperatureandV/IIIratiohavestrongeffectsonthepeakwavelengthandPLintensity.Thefull-widthathalf-maximum(FWHM)ofPLpeakincreaseswithhighergrowthrateofInGaAslayer.TheFWHMofthePLpeaklocatedat1039nmis20.1meV,whichgrowsat600°CwithV/IIIratioof42.7andgrowthrateof0.96mm/h.

简介：由使用0.15mGaAspHEMT(pseudomorphic高度电子活动性晶体管)技术，毫米波浪力量放大器微波的一个图案整体的集成电路(MMIC)是presented.With电路结构上的小心的优化，这个二阶段的电源放大器从33GHz与1dB的变化完成15.5dB的模仿的获得到超过在浸透的30dBm的模仿的产量电源能与最大的电源从3WDC供应被拉的37GHz.A26%.Rigorous的增加的效率(PAE)电磁的s

简介：Self-organizedIn0.5Ga0.5As/GaAsquantumislandstructureemittingat1.35μmatroomtemperaturehasbeensuccessfullyfabricatedbymolecularbeamepitaxy(MBE)viacycled(InAs)1/(GaAs)1monolayerdepositionmethod.Photoluminescence(PL)measurementshowsthatverynarrowPLlinewidthof19.2meVat300Khasbeenreachedforthefirsttime,indicatingeffectivesuppressionofinhomogeneousbroadeningofopticalemissionfromtheIn0.5Ga0.5Asislandsstructure.Ourresultsprovideimportantinformationforoptimizingtheepitaxialstructuresof1.3μmwavelengthquantumdot(QD)devices.

简介：Theself-assembledInAs/GaAsquantumdots(QDs)withextremelylowdensityof8×10~6cm~(-1)areachievedusinghighergrowthtemperatureandlowerInAscoveragebylow-pressuremetal-organicchemicalvapourdeposition(MOVCD).Asaresultofmicro-photoluminescence(micro-PL),forextremelylowdensityof8×10~6cm~(-1)InAsQDsinthemicro-PLmeasurementsat10K,onlyoneemissionpeakhasbeenachieved.ItisbelievedthattheInAsQDshaveagoodpotentialtorealizesinglephotonsources.

简介：Ap-typeAlAs(70.2nm)/16.5period［GaAs(3nm)/AlAs(0.7nm)］semiconductor/superlaticedistributedBraggreflector(DBR)hasbeengrownonn+-GaAs(100)substratebyV80Hmolecularbeamepitaxysystem.Experimentalreflectionspectrumshowsthatitscentralwavelengthis820nm,withthepeakreflectivityfor10-pairDBRofashighas96%,andthereflectionbandwidthofaswideas90nm.Weformeda20×20μm2squaremesatomeasuretheseriesresistanceusingwetchemicaletching.Fromthemeasurementresult,theseriesresistanceofabout50Ωisobtainedatamoderatedoping(3×1018cm-3).Finally,thedependenceoftheresistanceoftheDBRonthetemperatureisanalyzed.Fromtheexperimentalresult,itisfoundthatthemechanismofthelowseriesresistanceofthiskindofDBRmayincreasethetunnelingcurrentinthesemiconductor/superlatticemirrorstructure,whichwillresultinadecreaseinseriesresistance.

简介：<正>MimixBroadband公司推出了一种GaAsMMIC分谐波接收机。该接收机有一个三级平衡低噪声放大器(LNA)、一个镜相抑制分谐波逆平衡二极管混频器和集成本振(LO)缓冲放大器。使用这个镜相抑制混频器就无需在低噪声放大器之后再用一个带通滤波器来消除镜相频率下的热噪声。

简介：TheverticalandlateralinteractionsinamultisheetarrayofInAs/GaAsquantumdotsareanalyzedbyfiniteelementmethod(FEM).Itisshownthatduetotheeffectsofverticalinteraction,nucleationpreferstohappenaboveburiedquantumdots(QDs).Meanwhile,theeffectsoflateralinteractionadjustthespacingoflateralneighboringQDs.TheverticalcouplingbecomesstrongwithdeceasingGaAsspacerheightandincreasingnumberofburiedlayers,whilethelateralcouplingbecomesstrongwithincreasingInAswettinglayerthickness.Thephenomenonthat,aftersuccessivelayers,thespacingandsizeofQDsislandsbecomeprogressivelymoreuniformisexplainedaccordingtotheminimumpotentialenergytheory.

简介：ＳｐａｔｉａｌＤｉｓｔｒｉｂｕｔｉｏｎｏｆＥＬ２ＤｅｆｅｃｔｉｎＳｅｍｉ－ｉｎｓｕｌａｔｉｎｇＧａＡｓＲｕＱｉｏｎｇｎａ；ＬｉＧｕａｎｇｐｉｎｇａｎｄＨｅＸｉｕｋｕｎ（汝琼娜）（李光平）（何秀坤）（ＴｉａｎｊｎｇＥｌｅｃｔｒｏｎｉｃＭａｔｅｒｉａｌｓ...

简介：本文报道了分子束外延（MBE）生长的Be掺杂GaAs,通过改变Be掺杂源的温度我们得到了不同掺杂浓度的GaAs样品.利用原子力显微镜（AFM）和霍尔测试仪分别对样品的表面形貌和电学特性进行表征.特别的,在低温和随温度变化的光致发光谱中,随着掺杂浓度的增加与Be受主相关的辐射相应地加强.

简介：FourparallelGaAsphotoconductivesemiconductorswitches(PCSSs)weretriggeredsimultaneouslybyfour1064nmlaserbeams.Thetransientcharacteristicsoffourlinearelectricalpulseswereinvestigated.Whentheenergyoffourlaserbeamswere16.4mJ,15.6mJ,15.3m.J,and13.7mJ,respectively,fourstableelectricalpulsesofabout25nswidthand10nsrisetimewereobtainedatthesamebiasvoltageof8kV.Themaximumswitchingvoltageamplitudewas3.8kV.Withthetriggeringpulseenergyandbiasvoltagekeptconstant,thethreeGaAsPCSSsweretriggeredat10Hzlaserpulse.Themethodofsynchronizationcalculationwasgiven,andthesynchronizationoffourparallelGaAsPCSSswascalculatedtobe79ps.Theinfluenceofbiasvoltageandlaserenergyonthevoltageamplitudeofelectricalpulsewasanalyzed.Furthermore,relationshipbetweenthesynchronizationandthejittertimewasalsodiscussed.

简介：矿物晶体是天然物质，是由一种以上的元素以一定的几何结构排列构成，即使是同种元素构成的矿物晶体，因原子的结构形式不同，它们所具有的性质也完全不同，例如钻石和石墨、石墨的结构呈层状排列，相互重叠，结合较弱，容易变形，而经过高温高压深埋在地下150千米的钻石矿，

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简介：高功率固体激光装置对KDP晶体光学元件的基本要求是大口径、高精度面形质量、高激光损伤阈值、良好的表面粗糙度。但是KDP晶体本身具有质软、易潮解、脆性高、对温度变化敏感、易开裂等一系列不利于光学加工的特点，传统的研磨抛光法不适于加工高精度的大口径KDP元件。国外加工此类元件已广泛采用先进的单点金刚石车削技术（简称SPDT）。采用SPDT技术加工KDP晶体元件，主要存在3个方面的加工误差，即晶体的面形误差、表面粗糙度（包括表面疵病）以及小尺度波纹等。

简介：摘要：晶体与非晶体在电子材料领域扮演着至关重要的角色。晶体，如硅和锗，因其有序的原子结构，拥有独特的电学特性，被广泛应用于半导体器件中。例如，硅是目前最常用的半导体材料，全球超过90%的半导体设备都依赖于硅晶片。而量子点晶体，因其尺寸达到纳米级别，能精确控制电子的行为，为量子计算和高效太阳能电池的研发提供了可能。

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