ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1980.tb00271.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SUMMARYCarrier recombination at individual dislocations is investigated for the case of misfit dislocations at a heterojunction between Ga1–xAlxAs1–yPyepitaxial layers. Through the combined use of scanning transmission electron microscopy, electron beam induced current and cathodoluminescence analysis, it is shown that the non‐radiative and radiative recombination properties of dislocations are associated with their fine crystallographic configuration. The edge Lomer‐Cottrell dislocation is found to be electrically neutral. The absence of carrier recombination strongly suggests that core reconstruction may be important in eliminating dangling bonds and kink sites along the core of these dislocations. An undissociated dislocation with a Burgers vectorb=1/2a〈110〉 is proposed as the more likely configuration for the edge Lomer‐Cottrell dislocation. An asymmetry in the nonradiative recombination properties and crystallographic structure of the 60° dislocation is also reported

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1980.tb00272.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SUMMARYA high voltage electron microscope, equipped with scanning transmission (STEM) attachment, electron beam induced conductivity (EBIC) facilities, and electron energy loss spectrometer (ELS), has been used to investigate semiconductor devices. The capability of STEM to produce, simultaneously or sequentially, conductive and transmission images of the same specimen region, which can also be ELS analysed, is exploited in order to establish direct and unambiguous correlations between EBIC and STEM images of defective regions (dislocations and microplasma sites) in silicon devices.The results obtained are discussed in terms of correlations, resolution, contrast, and radiation damage; in addition, a comparison is made between this method and the other correlation methods based on EBIC/SEM (scanning electron microscope) and TEM (transmission electron microscope).

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1980.tb00273.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SUMMARYRecent developments in the application of the SEM to semiconductor assessment are described. Formulae are presented for the calculation of the mean carrier density injected by the electron beam. A procedure for the correction of diffusion length measurements for surface recombination is outlined. Measured diffusion lengths and lifetimes in GaP agree well. Lifetime measurements, when applied to the study of dislocations in GaP, show that recombination occurs mainly at a Cottrell atmosphere of impurities/defects surrounding the dislocation.

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1980.tb00274.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SUMMARYA technique for depth profiling of semiconductors is described based upon the measurement of induced junction currents as a function of beam energy. Using the known energy loss relation and electron hole pair generation rate it is possible to infer quantitative information about the semiconductor structures as a function of depth between ∼0·02 and ∼5 μm for silicon. Examples of the application of the technique to implanted and electron beam pulse annealed silicon and to a JFET transistor are described. Calculations of diffusion length limits, junction depths, poly‐silicon thickness, epitaxial layer thickness and surface recombination velocity are di

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1980.tb00275.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SUMMARYA method is described for obtaining two‐dimensional distributions of minority carrier lifetimes in semiconductor materials for optoelectronic applications. The novel features of the system are: on line analogue calculation of the lifetime from the decay of the cathodoluminescence signal after switching off the SEM electron beam; simultaneous computerized mapping of the signals obtained in this manner in the scanning electron microscope. Typically, it permits establishing a map of 1 mm2with 512 times 512 data points in 10 min for lifetimes down to 3 n

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1980.tb00276.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SUMMARYMinority carrier lifetime is one of the basic material properties in optoelectronic devices and material. Both the micrometer range dimensions of the devices and lifetime variations around defects in materials require a lifetime measurement technique with both high spatial and high temporal resolution. In order to meet these requirements a highly efficient cathodoluminescence (CL) measurement system has been developed consisting of a commercial scanning electron microscope extended for integral and spectral CL‐measurements and a streak camera with subnanosecond time resolution as time resolving detector. The lifetime is determined by evaluation of CL‐decay time after excitation of the specimen by an electron beam pulse, which is blanked in less than 50 ps by an adjustable plate capacitor. The CL‐light is collected by an adjustable, ellipsoidal mirror and can be dispersed in a vacuum monochromator. The monochromator exit slit is imaged on to the photocathode of the streak camera, which transforms the temporal distribution of the photon intensity into a lateral distribution on the camera phosphor screen after amplification by an integrated microchannel plate. By this technique it is possible to record the complete CL‐decay simultaneously, thus avoiding all measurement falsifications by system instabilities. The resulting intensity distribution is read out by a SIT vidicon camera with subsequent multichannel analyser, providing an intensity plot versus streak time in less then 1 min for each beam spot location. The technique is therefore well suited for lifetime mapping experiments. The best time resolution of the complete system achieved today is about 100 ps. Its performance is here demonstrated by measurements of the temperature dependence of the CL‐decay in a highly Se‐doped GaAs specimen in the temperature range from 90

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1980.tb00277.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SUMMARYA scanning optical microscope is described which exhibits a form of super‐resolution. Examples of its application to semiconductor device inspection are presente

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1980.tb00278.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SUMMARYThe contamination of Si integrated circuits during B diffusion is shown to produce an α‐Fe precipitate which electrically degrades p‐n junctions. The precipitates are shown to strain the Si lattice inducing dislocations which can glide to other parts of the cir

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1980.tb00279.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

SUMMARYThe electron beam induced current (EBIC) mode of the scanning electron microscope (SEM) has been used to characterize double heterostructure laser materials and devices in GaAs/Ga1–xAlxAs. Scanning the electron probe across the cleaved face of the laser structure shows that displacement of the p‐n junction with respect to the heterojunctions is not uncommon with displacements ∼ 1 μm occurring. Concurrent measurement of the minority carrier diffusion length gives very short lengths of 0·3–0·4 μm, differing from those in much thicker layers. Scanning the electron probe in the contact plane indicates clearly that long‐lived lasers exhibit marked heterogeneity during degradation. Considerable complexity and variation is recorded depending upon the fabrication details and degradation condi

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1980.tb00280.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY