摘要:

In this work we have used a dual implant and anneal process to significantly improve the crystalline quality of 0.3‐&mgr;m silicon on sapphire films while simultaneously minimizing the outdiffusion of free Al from the sapphire into the Si layer. The crystalline quality, as measured by MeV4He+ion channeling closely approached ⟨100⟩ bulk Si values and the Al concentration, as measured by secondary ion mass spectrometry, was less than 3×1015cm−3. An explanation for why similar techniques result in large amounts of aluminum outdiffusion when applied to 0.5‐&mgr; films is proposed.

ISSN:0003-6951    

DOI:10.1063/1.94033

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A mixture of nitric and hydrochloric acids was found to yield etch pits on mercury cadmium telluride crystals grown by chemical vapor transport using iodine or mercuric iodide as the transport agent. Two types of pits were observed by optical microscopy: triangular pyramidal and round saucer shaped pits. Transmission electron microscopy confirmed that two types of defects were present: dislocations and second phase occlusions. The present study suggests that the defects are near the crystal surface and therefore will probably not significantly affect the electrical characteristics.

ISSN:0003-6951    

DOI:10.1063/1.94034

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The photoconductivity of amorphous silicon films is shown to be enhanced by a factor of 25 at long wavelengths when the material is deposited on a rough, reflecting substrate. In a solar cell, this light trapping effect would produce a 4.5‐mA/cm2increase in the short circuit current.

ISSN:0003-6951    

DOI:10.1063/1.94035

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The cw laser activated flow method is applied to the planarization of phosphosilicate glass passivatedn‐channel metal‐oxide‐semiconductor field‐effect transistors with various device geometries. Flow is demonstrated over a range of raster scan velocities and at all principal CO2laser wavelengths. Device characteristics, namely, threshold voltage, junction breakdown voltage, and transconductance, are essentially unaffected by the laser irradiation, whereas the polycrystalline silicon interconnect resistance is reduced by about 20%. The effect of thermal conductivity of the phosphosilicate glass on the laser flow threshold is shown.

ISSN:0003-6951    

DOI:10.1063/1.94036

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The field dependence of electron beam induced current in thin oxide (22.5 nm) capacitors has been studied with a view of using the induced current for detecting defects in such devices. Results indicate that the induced current follows Fowler–Nordheim tunneling behavior when the field exceeding 4 MV/cm, and that a certain type of defect in thin oxide capacitors can be imaged with high contrast and low noise. A high current gain (∼103) of the induced current was also obtained. These findings open the possibility of acquiring information on the quality and reliability of composite metal‐insulator‐metal/semiconductor structures, and of achieving a high current for signal amplification.

ISSN:0003-6951    

DOI:10.1063/1.94037

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

We have studied the change in morphology of laser irradiated silicon wafers by annihilating the oxygen thermal donors and the oxidation‐induced stacking faults in order to verify the melting of the near‐surface regions. The laser beam used was of 1.06 &mgr;m with a diameter of 40 &mgr;m, generated from aQ‐switched neodymium:yttrium aluminum garnet (Nd:YAG) laser with a 150‐ns pulse width and at a repetition rate of 12 kHz. Laser beam irradiation above about 6 J/cm2annihilated both thermal donors and stacking faults, giving evidence of melting and suggesting that the annihilation of the thermal donors and of the stacking faults can be useful in studying the surface morphology in laser/electron beam irradiation.

ISSN:0003-6951    

DOI:10.1063/1.94038

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

Studies on amorphous siliconp‐ndiodes have shown that theplayers are photovoltaically active.Jscof up to 3.4 mA/cm2andVocof 780 mV have been observed. Detailed quantum efficiency measurements were performed as a function of bias voltage,p‐layer thickness, and boron doping. The data fit a simple depletion width model in which all photogenerated carriers created inside the depletion region are collected. An additional ‘‘reverse’’ barrier depletion width is assumed at the interface between the front transparent oxide electrode and theplayer to explain the results. A 10‐nm‐thickplayer typically used inp‐i‐ncells could collect up to 1 mA/cm2if the electric field in theplayer is greater than 105V/cm.

ISSN:0003-6951    

DOI:10.1063/1.94039

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

The high field (>30 kV/cm) electron drift velocity inn‐type (100) InP has been measured at temperatures from 95 to 400 K and electric field strengths up to 215 kV/cm using a fixed frequency (7.54 GHz) microwave time‐of‐flight technique. The velocity decreases monotonically with increasing electric field strength at all temperatures over the entire range of field strengths investigated. At 300 K the electron drift velocity in InP is 1.2 times the velocity in GaAs at 150 kV/cm, and increases to 1.34 times the velocity in GaAs when the field is lowered to 30 kV/cm.

ISSN:0003-6951    

DOI:10.1063/1.94040

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

A scanning cw argon ion laser has been used to rapidly heat Si in a fixed oxygen atmosphere to produce thin oxide layers on the surface. Analysis of the growth rate of these films reveals an enhancement over the normal thermal equilibrium rate of oxidation for silicon dioxide layers grown by furnace in the temperature range 850–1050 °C, and is thought to be a result of the photoionizing effect of the band‐gap photon flux. A simple model incorporating this characteristic is shown to qualitatively agree with the experimental results, and clearly indicates the importance of the density of broken Si–Si bonds in the oxidation reaction.

ISSN:0003-6951    

DOI:10.1063/1.94041

出版商:AIP    

年代:1983

数据来源: AIP

摘要:

In photothermal ionization spectroscopy both positive and negative photoconductivity responses have been reported from compensating centers neutralized by minority carriers generated by band‐edge light. Here, the response of compensating impurities in bothn‐type andp‐type high‐purity (‖NA−ND‖ ≊1010–1012cm−3) nuclear‐detector‐grade silicon and germanium is reported. Negative photoconductive responses from compensating impurities were observed only when the distance the photothermally generated majority carriers traveled before recapture by shallow levels was longer than the sample length (contact to contact). We propose that in high‐purity semiconductors, such as used in this study, it is the contact configuration that is responsible for the apparent rapid recombination of minority carriers which causes negative minority‐carrier photoconductivity.n+nn+orp+pp+structures allow multiple traversals through the sample by only majority carriers. The dependence of the band‐edge light generated excess carrier density on applied electric field supports this mechanism.

ISSN:0003-6951    

DOI:10.1063/1.94042

出版商:AIP    

年代:1983

数据来源: AIP