摘要:

Clean silicon (111) (7×7) surfaces at up to 1050°C have been reacted with nitrogen ions and neutrals produced by a low energy ion gun. The LEED patterns observed are similar to those previously reported for reaction of silicon (111) (7×7) with NH3. The nitrogenKLLpeak exhibits no shift or change in shape with nitride growth. At the same time the magnitude of the elemental siliconLVVpeak at 92 eV decreases progressively as a new peak at 84 eV increases. The position of both peaks appears to be independent of the degree of nitridation. Since the Auger spectra are free of oxygen and other impurities, these features can be attributed only to silicon, nitrogen, and their reaction products. Characteristic features of the Auger spectra are related to LEED observations and to the growth of microcrystals of Si3N4.

ISSN:0022-5355    

DOI:10.1116/1.570498

出版商:American Vacuum Society    

年代:1980

数据来源: AIP

摘要:

Complementary Auger electron spectroscopy (AES), secondary ion mass spectroscopy (SIMS), and x‐ray photoelectron spectroscopy (XPS) are used to evaluate low‐temperature wet and dry oxides and the oxide/semiconductor interfaces on polycrystalline GaAs. The dry oxides are found to be primarily Ga2O3and are relatively uniform in composition. The wet oxides are less uniform and mixed, with a more abrupt transition region that the dry oxide/GaAs interface. XPS data confirm the presence of Ga2O3in the dry oxide. In comparison, Ga2O3, As2O5are detected in the wet oxide layer. SIMS shows higher trace impurity concentrations in the wet oxide with some buildup at the oxide/GaAs interface. The relative performance of solar cells fabricated from these structures is discussed.

ISSN:0022-5355    

DOI:10.1116/1.570499

出版商:American Vacuum Society    

年代:1980

数据来源: AIP

摘要:

The chemistry and composition of grain boundaries in polycrystalline GaAs grown by liquid phase epitaxy (LPE) and molecular beam epitaxy (MBE) are examined using complementary Auger electron spectroscopy (AES), secondary ion mass spectroscopy (SIMS) and x‐ray photoelectron spectroscopy (XPS). The effects of an unintentional residual‐oxygen partial pressure during LPE growth are investigated in terms of grain boundary passivation. Depth‐compositional data verify the grain boundary localization of oxides using aninsitu, UHV fracturing technique. Indications of distributions of these oxides over the grain boundary are presented. The performances of Au Schottky barrier solar cells fabricated from the polycrystalline LPE and MBE GaAs are compared and differences are explained in terms of grain boundary activity.

ISSN:0022-5355    

DOI:10.1116/1.570500

出版商:American Vacuum Society    

年代:1980

数据来源: AIP

摘要:

We have carried out an investigation of the use of phosphosilicate glass (PSG) flow for integrated optical circuits. PSG layers of thicknesses ranging from 4 to 22 μm were chemically vapor deposited on V‐grooves in silicon substrates having a depth of 175 μm. The effect on the flow of (1) P2O5concentration in PSG layers (5–10 mol %), (2) ambient during flow (dry O2, wet O2, POCl3, and wet N2), (3) temperature (1000°–1200°C) and (4) time (30–120 min) of the process has been determined. The extent of flow, as measured by curvature of the rounded corners, has been plotted against PSG layer thickness and reflow time. Radii of curvature up to 36 μm through 70° bends have been measured.

ISSN:0022-5355    

DOI:10.1116/1.570501

出版商:American Vacuum Society    

年代:1980

数据来源: AIP

摘要:

The radiation used in x‐ray lithography spans a rather broad range, from about 4 to 50 Å. At the short wavelength end, transmission through mask membranes and vacuum windows is high, and minimum linewidth is of the order of 1/2 μm. At the long wavelength end, mask selection is limited, exposure is done in vacuum and minimum linewidth is about 100 Å. At intermediate wavelengths, one can make numerous tradeoffs among resolution, system configuration, masks and resists. X‐ray lithography at the AlKwavelength (8.34 Å) is compared with scanning electron beam lithography from the point of view of exposure time, assuming a step‐and‐repeat strategy. The use of gap adjustment to compensate for homogeneous substrate distortion may be an important advantage of x‐ray lithography relative to other parallel exposure techniques.

ISSN:0022-5355    

DOI:10.1116/1.570502

出版商:American Vacuum Society    

年代:1980

数据来源: AIP