摘要:

100‐&mgr;m silicon‐on‐insulator structures have been achieved by first utilizing silicon molecular beam epitaxial (Si MBE) growth on porous silicon and subsequently oxidizing the porous silicon through the patterned Si MBE film windows. A Si beam method is used for the low‐temperature surface cleaning of porous silicon prior to Si MBE growth. By using a two‐step growth technique, the Si MBE film shows good crystallinity checked by Rutherford backscattering channeling spectroscopy and cross‐sectional transmission electron microscopy. An electron mobility of 1300 cm2 V−1 s−1with a doping concentration of 6×1015cm−3has been achieved.

ISSN:0003-6951    

DOI:10.1063/1.96789

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

We report a study of the electrical properties of Schottky barrier heights of column IIB metals (Hg, Cd, and Zn) on chemically cleanedn‐type InP(100). Hg/InP diodes were formed by using a commercially available mercury probe, while Cd/InP diodes and Zn/InP diodes were fabricated by electroplating techniques. Dark forward bias current‐voltage as well as dark reverse bias capacitance‐voltage measuring techniques were used to characterize the samples. The barrier heights were found to be 0.92, 0.62, and 0.43 eV for Hg/n‐InP, Cd/n‐InP, and Zn/n‐InP, respectively. The barrier heights for Hg/n‐InP and Cd/n‐InP are higher than commonly thought possible onn‐type InP.

ISSN:0003-6951    

DOI:10.1063/1.96790

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Using InGaAs for the base and InAlAs for the emitter and collector barriers, we have fabricated the first hot‐electron transistor in this material system. We have shown that 1.6% of the injected hot electrons can be transported ballistically through a 0.3‐&mgr;m‐thick In0.53Ga0.47As plus 800‐A˚‐thick InAlAs barrier layer at 77 K giving rise to an average mean free path of 920 A˚. An energy spread of 130 meV was observed for the ballistic electrons injected at about 700 meV above the thermal equilibrium conditions. The values of collector barrier heights measured are in reasonable agreement with those deduced independently from thermionic emission studies in InGaAs gate, InAlAs/InGaAs capacitor structures.

ISSN:0003-6951    

DOI:10.1063/1.96791

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

The Schottky barriers formed for a wide range of metals on (110)n‐CdTe surfaces have been studied using current‐voltage and capacitance‐voltage techniques. The surfaces were prepared by cleaving in ultrahigh vacuum, cleaving in air, and chemical etching. The electrical barriers are drastically influenced by oxide layers on the surface. Most metals on the chemically etched surfaces yield barriers having values around 0.7 eV but Mn, Cr, and V are notable exceptions, yielding ohmic or low barrier contacts. Microscopic interactions of these interfaces have also been studied by soft x‐ray photoemission using synchrotron radiation. Detailed comparisons of the microscopic interaction of Ag and Mn with the clean and oxidized surfaces, using photoemission, are presented. In contrast to the behavior of Ag, the Mn overlayer completely reduces the CdTe native oxide layer, resulting in lower barrier contacts.

ISSN:0003-6951    

DOI:10.1063/1.96792

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Rapid thermal annealing of arsenic implanted ⟨100⟩ silicon single crystals has been studied by Rutherford backscattering/channeling spectrometry, and Hall effect/resistivity measurements, combined with layer removal. Redistribution of the implanted arsenic was followed as a function of anneal time (6–60 s including temperature rise time) and implanted peak concentration (3–10×1020cm−3) at temperatures of 1050 and 1090 °C. The maximum concentration of electrically active arsenic was found to be 2–3×1020cm−3independent of anneal time and implanted peak concentration. Fast arsenic redistribution was observed to take place within the first 20 s of annealing. Complete arsenic activation occurred by means of rapid redistribution to the solubility limit.

ISSN:0003-6951    

DOI:10.1063/1.96793

出版商:AIP    

年代:1986

数据来源: AIP

摘要:

Powder metallurgy processed Nb3Sn(Ti) superconducting wires were fabricated with Snxwt. % Ti cores for 0≤x≤3, 16 or 22 vol % cores, and a Cu 45 wt. % Nb composite. The processing used swaging, cold hydrostatic extrusions, wire drawing and heat treatments of 750 °C for two to four days. Nominal areal reductions of 104were used. Hydride‐dehydride Nb and rotating electrode processed Nb powders gave the same performance. Overall critical current densitiesJcwere measured between 4.2 and 1.8 K for applied fields up to 23 T.Jcincreased with increased Ti and/or Sn content. The Nb3Sn(Ti) wires using a Sn 3 wt. % Ti, 22 vol % core gaveJc>104A/cm2at 20 T and 4.2 K andJc=104A/cm2at 23 T at 1.8 K. Removal of the precompression of the matrix increasedJcby about a factor of 2 at 20 T and 4.2 K.

ISSN:0003-6951    

DOI:10.1063/1.96794

出版商:AIP    

年代:1986

数据来源: AIP

ISSN:0003-6951    

DOI:10.1063/1.97042

出版商:AIP    

年代:1986

数据来源: AIP

ISSN:0003-6951    

DOI:10.1063/1.97041

出版商:AIP    

年代:1986

数据来源: AIP