556 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "Etching"  
Results: 1 - 24 next
open access

Array automated assembly: Phase 2. Quarterly report

Description: An analysis was made of cost trade-offs for shaping modified square wafers from cylindrical crystals. For reasonably expectable silicon and sheet costs, the optimum shape will be nearer a circle than a square. Tests were conducted of the effectiveness of texture etching for removal of surface damage on sawed wafers. Four glass systems have survived preliminary screening tests for use as edge masking dielectrics. These include beta-spodumen, MgO-Al/sub 2/O/sub 3/ borosilicate, baria and titania … more
Date: February 1, 1978
Creator: Taylor, W.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

(Preoxidation cleaning optimization for crystalline silicon)

Description: A series of controlled experiments has been performed in Sandia's Photovoltaic Device Fabrication Laboratory to evaluate the effect of various chemical surface treatments on the recombination lifetime of crystalline silicon wafers subjected to a high-temperature dry oxidation. From this series of experiments we have deduced a relatively simple yet effective cleaning sequence. We have also evaluated the effect of different chemical damage-removal etches for improving the recombination lifetime a… more
Date: January 1, 1991
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Phase 2 of the array automated assembly task for the Low Cost Solar Array Project. Final report, October 1, 1978-October 30, 1979

Description: The process sequence for the fabrication of dendritic web silicon into solar panels has been modified to include aluminum back surface field formation. Sputtering is the preferred method for depositing the aluminum. Plasma etching has been shown to be a feasible technique for pre-diffusion cleaning of the web. This would replace wet chemical cleaning. Several contacting systems have been studied. The total plated Pd-Ni system (Motorola Process) is not compatible with our process sequence; howev… more
Date: January 1, 1979
Creator: Campbell, R. B.; Davis, J. R.; Ostroski, J. W.; Rai-Choudhury, P.; Rohatgi, A.; Seman, E. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Los Alamos upgrade in metallographic capabilities

Description: The Los Alamos Wing 9 Hot Cell Facility is in the process of upgrading their metallographic sample preparation and examination capability. The present capability to grind, polish and etch samples from reactor fuels and materials has been in operation for 18 years. Macro photography and alpha and beta-gamma autoradiography are an important part of this capability. Some of the fast breeder reactor experiments have contained sodium as a coolant. Therefore, the capability to distill sodium from som… more
Date: January 1, 1985
Creator: Ledbetter, J. M.; Dowler, K. E. & Cook, J. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Phase 2 of the automated array assembly task of the Low-Cost Silicon Solar Array Project. Technical quarterly report No. 6, 1 October 1979-31 December 1979

Description: The ion implantation, metallization, and plasma etching processes are highlighted. Replacement of the hydrocarbon vacuum pump oils in the ion implanter with perfluorinated polyether pump oils has decreased, but not eliminated the formation of a carbonaceous surface layer on implanted wafers. Simulated unanalyzed beam ion implantation of boron for p-on-n cell fabrication has shown preliminary favorable results, showing better performance than control analyzed beam boron implants. An ion milling … more
Date: January 1, 1979
Creator: Coleman, M. G.; Pryor, R. A.; Sparks, T. G. & Saltzman, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Evaluation of different polymers for fast neutron personnel dosimetry using electrochemical etching

Description: There is considerable optimism for the enhancement by electrochemical etching of fast neutron-induced recoil tracks in polycarbonate for the purpose of personnel dosimetry. The threshold energy, however, is rather high. A desirable improvement would be to lower this energy below 1 MeV. With this objective in mind, we have commenced an investigation of cellulose acetate, triacetate, and acetobutyrate in addition to polycarbonate. These cellulose derivatives are chemically more reactive and physi… more
Date: January 1, 1977
Creator: Gammage, R.B. & Cotter, S.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Boron arsenide thin film solar cell development. Final report

Description: Pyrolytic decomposition of diborane and arsine has been used in attempts to grow polycrystalline BAs films. This method, however, produced only amorphous films for deposition temperatures below 920/sup 0/C and polycrystalline boron subarsenide (B/sub 12/As/sub 2/) flms for deposition temperatures above this value. The amorphous films have been determined to have a significant arsenic content but the actual stoichiometry was not obtained. The films were adherent on single crystal sapphire (0001)… more
Date: September 1, 1980
Creator: Boone, J.L. & Van Doren, T.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Process development for automated solar cell and module production. Task 4: automated array assembly

Description: The scope of work under this contract involves specifying a process sequence which can be used in conjunction with automated equipment for the mass production of solar cell modules for terrestrial use. This process sequence is then critically analyzed from a technical and economic standpoint to determine the technological readiness of each process step for implementation. The process steps are ranked according to the degree of development effort required and according to their significance to t… more
Date: June 30, 1980
Creator: Hagerty, J.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Fundamental studies of grain boundary passivation in polycrystalline silicon with application to improved photovoltaic devices. A final research report covering work completed from February-December 1979

Description: Several aspects of the electrical properties of silicon grain boundaries have been studied. The temperature dependence of the zero-bias conductance and capacitance of single boundaries has been measured and shown to be in good agreement with a simple double depletion layer/thermal emission (DDL/TE) model developed to predict the transport properties of such structures. In addition, it has been shown that deconvolution of the I-V properties of some boundaries via a deconvolution scheme suggested… more
Date: February 1, 1980
Creator: Seager, C. H. & Ginley, D. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigation of proposed process sequence for the array automated assembly task: Phase II. Quarterly technical progress report for quarter ending December 29, 1979

Description: A sulfur hexaflouride plasma etch was investigated as a possible surface treatment to improve the performance of the cell, the Radiation Technology Infrared Furnace was qualified for use in the process sequence, and work was initiated on junction clean up by laser scribing through the junction. An evaluation of the minority carrier diffusion length of silicon crystals received from various vendors was also included in this quarters activities. Results are presented and discussed.
Date: February 1, 1980
Creator: Mardesich, N.; Bunyan, S. & Sipperly, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Selected etching and annealing properties of Brazilian quartz crystals for solid state track recorder applications

Description: The etching and annealing properties of Brazilian quartz crystals are under investigation to determine their suitability for use as solid state track recorders (SSTR) and damage monitors in nuclear reactor environments, where temperatures and neutron fluences are high. Observer objectivity in counting fission tracks has been established at the 1 to 2% level, and a method of standardizing chemical etching from one sample of quartz to another has been found. A method has also been found to make c… more
Date: January 1, 1981
Creator: Roberts, J.H.; Gold, R. & Ruddy, F.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Surface treatment of lead glass microsphere

Description: The structural arrangement of a hydrated glass surface depends on the composition, thermal history and surface treatment. This paper considers the surface treatment of a lead glass with weak and strong acid solutions and in particular hydrogen peroxide, to give a microscopically clean microsphere.
Date: May 21, 1980
Creator: Andrews, J.E. Jr. & Koo, J.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Optimization of electrochemical-etching parameters for highly sensitive CR-39 fast neutron dosimeters

Description: Voltage gradient and frequency were studied for their influence on the electrochemical etching of CR-39 plastic irradiated with fission spectrum, fast neutrons. A power supply having outputs of up to 1.5 kV (rms) and 5 kHz was used. Differential leakage current measurements under non-etching conditions indicated that the optimal values in electrochemical etching would be 20 kV/cm and 1.3 kHz. That these parameters produced a maximum sensitivity was verified in subsequent electrochemical etching… more
Date: January 1, 1981
Creator: Gammage, R.B. & Chowdhury, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development of polycrystal GaAs solar cells. Quarterly technical progress report No. 2 for May 1-July 31, 1979

Description: Investigation of grain boundaries in GaAs, growth of small-grained GaAs, and solar cell fabrication on small-grained material continued this quarter. Some highlights were the fabrication of MS cells of small-grained GaAs grown on Mo, the fabrication of MIS cells using spin-on oxides, and the determination of interface state density at a high-resistance grain boundary. Initial measurements show that series resistance and shunt leakage seriously degrade the performance of cells made from small-gr… more
Date: September 1, 1979
Creator: Miller, D. L.; Cohen, M. J.; Harris, Jr., J. S.; Ballantyne, J.; Hoyte, A. & Stefanakos, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High-aspect-ratio silicon-cell metallization technical status report. Final report

Description: Two features of the silicon concentrator solar cell are addressed which affect output at high concentration levels. The first is the development of narrow but high electroplated grid lines with improved conductivity. The object is a reduction in cell series resistance without increase in shadowing. This goal is accomplished by electroplating through a thick photo resist mask to produce lines .7 mil wide by .7 mil high. Advance pulse plating techniques are combined with pure silver plating baths… more
Date: January 1, 1982
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Thin film gold etchant formulation and rinse removal. Final report

Description: The chemistry of gold etchant solutions used in photolithography of thin film networks (TFNs) for hybrid microcircuits was reviewed. The formulation and operating limits were revised to ensure that the initial solution makeup is always within required values for iodine concentration and specific gravity and that the etchant will not be used for an extended period of time. Rinsing procedures for removal of the gold etchant from the TFNs were evaluated. Increasing the rinse time beyond 15 seconds… more
Date: July 1, 1980
Creator: Raut, M. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The influence of the substrate surface on the nucleation and growth of superconducting thin films

Description: The quality of epitaxially grown superconducting thin films is dependent on the nature of the substrate surface. In this study, the surface of <100> oriented SrTiO{sub 3} single crystals was modified by mechanical polishing, thermal annealing and chemical etching. A study of the YBa{sub 2}Cu{sub 3}O{sub 7-x} thin films grown on these substrates showed that high quality superconducting films were obtained when the substrate surface was highly oriented in the <100> direction and was also microsco… more
Date: January 1, 1989
Creator: Basu, S.N.; Bordes, N.; Rollett, A.D.; Cohen, M.R. & Nastasi, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Low-cost solar antireflection coatings. Annual report, 24 July 1978-24 September 1979

Description: Production processes for low-cost organic antireflection (AR) coating and etched AR coating on glass are being developed and improved. The etched AR coating process has been scaled-up to etch full-size glass panes but the chemical control of the etching solution remains a problem. Analytical methods including high pressure liquid chromatography (HPLC), flame excited atomic absorption, infrared spectroscopy, Coulter counter techniques, and liquid index of refraction measurements were examined fo… more
Date: October 1, 1979
Creator: Lin, R. J.H.; Lee, J. C. & Zimmer, P. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Photoelectronic properties of zinc phosphide crystals, films, and heterojunctions. Quarterly progress report No. 11, October 1-December 31, 1981

Description: Variations in crystal growth techniques are continuing with the goal of: (1) improving single crystal quality; and (2) producing variations in crystal properties by doping and post-growth variations of stoichiometry. DLTS measurements using Mg/Zn/sub 3/P/sub 2/ Schottky diodes gave information on three deep levels between 0.55 and 0.66 eV above the valence band in sublimation grown crystals with densities in the 10/sup 15/ to 10/sup 16/ cm/sup -3/ range, and a shallower level at 0.12 eV with a … more
Date: January 1, 1981
Creator: Bube, R.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Sequential deposition etch techniques for the selective deposition of tungsten

Description: We report on the use of a deposition/etch approach to the loss of selectivity problem, using high activity fluorine chemistries in the etch step. Proof-of-concept experiments were initially performed in a hot wall system, the excellent results obtained lead us to prove out the concept in a commercially available cold wall Genus reactor. We observed that WF{sub 6} is ineffective as an etchant of W. The technique has been able to produce perfectly selective depositions 1 micron thick in both hot … more
Date: January 1, 1991
Creator: Fleming, J.G.; Omstead, T.R. & Dominguez, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Low-cost epitaxial techniques for solar-cell fabrication. Quarterly technical progress report No. 1, September 26, 1979-December 24, 1979

Description: During the frst quarter, a candidate low-cost silicon substrate, designated upgraded metallurgical grade (UMG) silicon, was obtained. The electrical, physical, and structural properties of three grades of this material were measured. An initial epitaxial growth technique was standardized and qualified for application to the growth of diagnostic and solar-cell structures. Such structures were grown on the three UMG grades of substrates and the properties of these layers were compared to those of… more
Date: January 1, 1980
Creator: D'Aiello, R. V. & Robinson, P. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
Back to Top of Screen