摘要:

The possibility of producing solar cells using rapid thermal processing (RTP) was reported in recent years. This process was applied with good results topn‐solar cells. In this work we used the RTP technique for the metal‐insulator‐semiconductor (MIS) inversion layer cells. Simultaneously with the growth of the tunneling oxide at the front side ap+/p‘‘high‐low’’ junction forms by alloying the Al into Si at the back contact. The efficiencies reached with this process are about 15%. ©1995 American Institute of Physics. 

ISSN:0003-6951    

DOI:10.1063/1.115207

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The diffusion characteristics and incorporation characteristics of Zn dopants in OMVPE‐grown InP are studied. The Zn diffusion constant depends strongly on concentration and increases by four orders of magnitude in the Zn concentration range 2×1018–8×1018cm−3. This drastic concentration dependence of the Zn diffusion constant is shown to determine the Zn incorporation characteristics during OMVPE growth. A spread of Zn dopants into intentionally undoped regions may result at high Zn doping concentrations in InP. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.115279

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The use of a low temperature grown GaAs buffer layer beneath the channel of a metal‐semicon‐ ductor field‐effect transistor is shown via computer simulation to reduce ion‐induced charge collection by two or more orders of magnitude. This reduction in collected charge is expected to reduce the heavy ion soft error rate by four to seven orders of magnitude in GaAs integrated circuits, and could have significant implications for the applicability of GaAs technology in space‐based systems. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.115280

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

Silicon thermal oxidation was used to characterize the interaction of Si interstitials with a Si1−xGexlayer and with B in Si1−xGex. Diffusion of B in a Si marker layer, positioned under a Si1−xGexlayer, was monitored as excess Si interstitials were injected into the bulk by the oxidation of the Si capping layer (T=850 °C,t=18 min). The Si1−xGexlayer did not affect the oxidation‐enhanced diffusion of B in the Si marker layer. Hence, Si1−xGex(x<0.30) does not appear to be a strong sink for Si interstitials. In addition, the enhancement from Si thermal oxidation (T=800 °C,t=60 min) of the measured B diffusivity in Si1−xGexis similar to that in Si. This indicates that, as in Si, the mechanism for B diffusion in Si1−xGex(x<0.18) primarily involves Si interstitials. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.115281

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

This letter discusses the effects of a moderate magnetic field applied to a SQUID magnetometer and introduces the invention of the ‘‘flux dam.’’ A flux dam is a weak link or Josephson junction in series with the pickup loop which allows magnetic flux to enter and leave the inside of the superconducting loop easily for moderate changes in magnetic field. This largely prevents the flux lines from entering and being pinned in the superconducting parts of the magnetometer which would create extra low frequency noise. SQUID magnetometers with flux dams in the pickup loop can be operated in the Earth’s magnetic field without a significant increase in low frequency flux noise. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.115282

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

Thin films of YBa2Cu3O7−&dgr;were sequentially grown on both sides of 3 in. diameter LaAlO3substrates by a single‐source MOCVD technique to facilitate the fabrication of double‐sided high temperature superconductor microwave devices. YBCO films on both sides of the LaAlO3substrates had thicknesses greater than 4000 A˚,Tc’s of 87–88.5 K, and microwave surface resistances as low as 23 m&OHgr; at 94 GHz and 77 K (scaling to 260 &mgr;&OHgr; at 10 GHz). It was found that the substrate temperature, brought to the desired value by radiant heating, played a critical role in the deposition of very low surface resistance YBCO films. Microwave bandpass filters with a 19‐pole forward coupled configuration were fabricated from these films. The filters showed excellent performance with dissipation losses as low as 0.5 dB. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.115283

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

We present the measurement of the sticking coefficient of Ba atoms on a MgO substrate by resonant laser induced fluorescence. The substrate is used as a target for a thermal atomic beam of barium while a laser crosses the substrate and counterpropagates to the atomic beam monitoring its velocity profile. A signal corresponding to negative velocity atoms with respect to the beam direction allows to determine the sticking coefficient. It resulted equal to 0.76 ±0.05. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.115284

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

Extraordinary magnetoresistance effect has been found in Ni/Co sputtered multilayers. Magnetoresistance values higher than 130% are achieved at room temperature with a saturation magnetic field of 35 Oe, using a particular arrangement of contacts. The large anisotropic magnetoresistance and the low coercivity of these samples are the origin of such an outstanding property. The results reported here seem to have promising applications in magnetoresistive devices. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.115285

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

Thin film ferroelectrics with polarization gradients normal to the growth surface readily form when gradients in temperature, strain, or composition are coupled to the polarization vector in ferroelectric materials. This letter describes the formation of thin films of potassium tantalum niobate with graded polarizations obtained by grading the tantalum to niobium ratio of the ferroelectric phase. Unlike a simple structure consisting of laminated layers of ferroelectric material, the polarization gradient which forms breaks the natural symmetry of the ferroelectric material at any given plane, resulting in a self‐poling of the structure subsequent to excitation by an oscillatory electric field. Once poled, the devices reveal a measurable potential across the structure which varies with temperature. ©1995 American Institute of Physics.

ISSN:0003-6951    

DOI:10.1063/1.115286

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The omission of a key reference (Ref. 2) in the authors’ earlier publication (Ref. 1) is noted. The major conclusion of (Ref. 2) was the same as that of the authors’ in (Ref. 1), namely, that surface steps generated by dislocation glide play an important role in the morphology in Si1−xGexfilms. (AIP)

ISSN:0003-6951    

DOI:10.1063/1.115287

出版商:AIP    

年代:1995

数据来源: AIP