摘要:

What started five years ago as a small workshop on compound semiconductor electronics now has grown to an international conference focusing on fundamental aspects of semiconductor interfaces and surfaces. A discussion is presented of the changing emphases, experimental techniques, and technological trends in the field as reflected by the evolution of this conference series. The novel meeting format of PCSI‐6 is described which allowed ample discussion of a large number of related papers while minimizing the ’’second class feeling’’ of poster presentations. A survey of participants critically

ISSN:0022-5355    

DOI:10.1116/1.570169

出版商:American Vacuum Society    

年代:1979

数据来源: AIP

摘要:

Formation and properties of binary compounds made by thin film interactions at temperatures well below the melting point of the various components were recently studied. Several aspects concerning such compounds are still, however, unclear; among which are (a) the mechanism responsible for the growth, (b) which phase is formed first, and (c) why not all the compounds predicted by the phase diagram were observed. We review the literature and suggest that the processes occurring at the interfaces control the phase formed. This conclusion is supported by new experimental data concerning the stability of the various phases as a function of the temperature and/or the sample composition.

ISSN:0022-5355    

DOI:10.1116/1.570170

出版商:American Vacuum Society    

年代:1979

数据来源: AIP

摘要:

The initial stage of silicide formation at the Pd/Si interface has been investigated during Pd deposition on the Si(111) surface using a combination of AES and TEM techniques. The formation of silicide was found to change the valence state of Si significantly as observed from the shape change of the SiLVVAuger spectra. The ratios of the normalized peak intensities were used to calibrate the composition and the thickness of the reacted layer. The calibration results coupled with TEM phase identification showed uniform formation of the Pd2Si compound even at room temperature up to about 10 Å Pd coverage. Using thin Pd coverages of about 10 Å, epitaxial growth of Pd2Si was not observed on sputter‐cleaned Si surfaces. Crystalline order was clearly observed at the Pd2Si/Si interface in annealed samples with less than 4 Å Pd2Si, indicating a relatively sharp interface with no significant amorphous‐like structural disorder.

ISSN:0022-5355    

DOI:10.1116/1.570171

出版商:American Vacuum Society    

年代:1979

数据来源: AIP

ISSN:0022-5355    

DOI:10.1116/1.570172

出版商:American Vacuum Society    

年代:1979

数据来源: AIP

摘要:

The surface of epilayers grown by chemical vapor deposition (CVD) cannot be characterizedinsituby RHEED, LEED, or Auger spectroscopy methods used for molecular beam epitaxy. But, unlike the epilayers grown by molecular beam epitaxy, those grown by CVD method have their crystallographic and electric properties controlled by the characteristics of a 4–20‐μm‐thick motionless gas layer called boundary layer. Samples of the boundary layer can be probed as a function of the distance above the growth surface and analyzed by gas phase chromatography in the case of silicon epitaxy in order to measure concentration and concentration gradient of pertinent chemical species close to the growth surface. This analysis allows us to explain the behavior of the growth rate, the kinetics of the incorporation of impurities and the crystallographic quality of eqilayers as a function of the growth parameters. General results can be used to explain most cold wall reactor behavior. GaAs and InP materials grown by the organometallic method are treated as examples.

ISSN:0022-5355    

DOI:10.1116/1.570173

出版商:American Vacuum Society    

年代:1979

数据来源: AIP

摘要:

A novel structure, which is both a lattice‐matched heterostructure and a Schottky barrier, is fabricated by epitaxial growth of (111) oriented HgSe on (0001) oriented CdSe. Hydrogen transport CVD is used, with a HgSe source temperature of 420°C and a CdSe substrate temperature of 330°C. Single crystal growth was obtained. Of the two orientations possible for the crystal symmetries involved, only one was observed for a given specimen. The ’’Schottky barrier’’ height for this lattice‐matched heterostructure is 0.73±0.02 eV as measured by the photoresponse method. This uncertainty is substantially less than is usual for Schottkies. The magnitude is greater by about one‐quarter volt than is achievable with the most electronegative elemental metal, Au, in qualitative agreement with work function arguments.

ISSN:0022-5355    

DOI:10.1116/1.570174

出版商:American Vacuum Society    

年代:1979

数据来源: AIP

摘要:

Total reflection x‐ray diffraction studies of Al−Ge(100) interfaces are made.(AIP)

ISSN:0022-5355    

DOI:10.1116/1.570175

出版商:American Vacuum Society    

年代:1979

数据来源: AIP

摘要:

An estimate for the minimum (Bardeen limit) and maximum (Schottky limit) of the interface index,S, is calculated. It is shown that current measurements on highSmaterials are near or at the maximum value forS.

ISSN:0022-5355    

DOI:10.1116/1.570176

出版商:American Vacuum Society    

年代:1979

数据来源: AIP

摘要:

New evidence for a defect mechanism which is responsible for pinning states within the band gap on the (110) surfaces of the III–V compounds is presented. Investigations of column III metals on bothn‐ andp‐type GaAs revealed a systematic difference in surface Fermi energy stabilization in the gap withp‐type samples pinning 0.25 eV belown‐type samples. Several current models and theories of Schottky barriers are discussed in terms of both the results given in this paper and previously reported data.

ISSN:0022-5355    

DOI:10.1116/1.570178

出版商:American Vacuum Society    

年代:1979

数据来源: AIP

摘要:

Local interface chemistry is important to understand before proceeding to unravel the electronic properties of interfaces. Characterization of the intrinsic aspects of reactions and interdiffusion is also important to understand possible device size limitations. Various types of local reactions are possible and we have investigated these with surface sensitive photoemission and photoyield spectroscopy using synchrotron radiation excitation. We show for both compound semiconductor and for oxide surfaces that reactions can occur which locally determine the chemical phases present. The heat of these reactions can drive the interdiffusion process. We present results for the important systems Al–GaAs, Al‐oxidized GaAs and Al–SiO2. We compare these results with our previous results for Ge and Ga on GaAs as well as those obtained by others. We demonstrate that theI–Vbehavior of Ga onp‐GaAs is ohmic and attribute this non‐schottky character to As diffusion and vacancy production at the interface. Diffusion can clearly be identified as distinct from island formation by analyzing the core photoelectron line shape; Ge grown on GaAs(110) at differing substrate temperatures provides an illustrative example. Interfacial reactions are observed in real time for Al2O3formation by Al reduction of oxidized Si.

ISSN:0022-5355    

DOI:10.1116/1.570179

出版商:American Vacuum Society    

年代:1979

数据来源: AIP