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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

Heat exchanger method: ingot casting; fixed abrasive method: multi-wire slicing (Phase II). Silicon sheet growth development for the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project. Quarterly progress report No. 1, November 21, 1977--December 31, 1977

Description: A high degree of crystallinity has been achieved in ingots cast. Since most of the growth took place near the solidification temperature, the top portion of the ingot was solidified by freezing from the surface. The thickness of this layer was reduced with the control of thermal flow characteristics in the furnace. The crucibles used in this study have a nonuniform bottom which is not conducive to proper heat transfer during solidification. In an effort to achieve high packing density of solar … more
Date: January 6, 1978
Creator: Schmid, F. & Khattak, C.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Phase 2 of the Automated Array Assembly Task of the Low-Cost Silicon Solar Array Project: Annual Report

Description: This report presents the results of investigations and analyses of an advanced process sequence for manufacturing high efficiency solar cells and modules in a cost-effective manner. The entire process sequence is presented and discussed step by step. Emphasis is on process simplicity and minimizing consumed materials. The process sequence incorporates texture etching, plasma processes for damage removal and patterning, ion implantation, low pressure silicon nitride deposition, and plated metal.… more
Date: November 1, 1978
Creator: Coleman, M. G.; Grenon, L. P.; Pastirik, E. M.; Pryor, R. A. & Sparks, T. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis and evaluation of processes and equipment in Tasks II and IV of the Low-Cost Solar Array Project. Quarterly report, April-July 1978

Description: The significant economic data for the current production multiblade wafering and inner diameter slicing processes were tabulated and compared to data on the experimental and projected Varian multiblade slurry, STC ID diamond coated blade, Yasunaga multiwire slurry and Crystal Systems fixed abrasive multiwire slicing methods. Cost calculations were performed for current production processes and for 1982 and 1986 projected wafering techniques.
Date: November 1, 1978
Creator: Goldman, H. & Wolf, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Continuous Czochralski process development. LSSA Large Area Silicon Sheet Task. Quarterly report No. 3, April--June 1978

Description: A Czochralski crystal growing furnace is being set up to permit installation of a continuous molten silicon feed apparatus. Numerous modifications have been designed and constructed to convert a Varian 2898A furnace to a continuous mode of operation. New laboratory facilities to house the continuous furnace were prepared and assembly of the furnace has been completed. Furnace checkout will be carried out early in the next quarter. Economic modeling of the continuous Czochralski process has cont… more
Date: July 1, 1978
Creator: Rea, S.N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Continuous Czochralski growth: silicon sheet growth development of Large Area Silicon Sheet Task of the Low-Cost Silicon Solar Array Project. Second quarterly progress report, January 1--March 31, 1978

Description: This project is directed toward the development of equipment and processes to produce single crystal solar silicon by a continuous Czochralski (CZ) method. ''Continuous'' is defined as the production of at least 100 kilograms of crystal from a single melt container. The approach to be taken is to suitably modify a Hamco CG2000 crystal grower to demonstrate that continuous CZ growth is feasible by the periodic replenishment of the melt container and the removal of grown cryst… more
Date: January 1, 1978
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Delayed fracture of silicon. Silicon sheet growth development for the Large Area Silicon Sheet Task of the Low Cost Silicon Solar Array Project. Final report

Description: Bar specimens were cut from ingots of single crystal silicon, and acid-etched prior to testing. Artificial surface flaws were introduced in specimens by indentation with a Knoop hardness tester. The specimens were loaded in four-point bending to 95% of the nominal fracture stress, while keeping the surface area, containing the flaw, wet with test liquids. No evidence of delayed fracture, and, therefore stress corrosion, of single crystal silicon was observed for liquid environments including wa… more
Date: March 31, 1978
Creator: Chen, T. J. & Knapp, W. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Slicing of silicon into sheet material. Silicon sheet growth development for the large area silicon sheet task of the Low Cost Silicon Solar Array Project. Tenth quarterly report, June 19--October 27, 1978

Description: The limits of blade tolerances are defined. The standard blades are T-2 thickness tolerance: T-O blades are unacceptable. Further testing is necessary to demonstrate feasibility or infeasibility of T-1 blades. Good results have been obtained by using a slurry fluid consisting of mineral oil and a lubricity additive. Cost would be about $0.25 per gallon per run, 1/4 of the cost goal. Adjustments of the formulation and fine tuning of the cutting process with the new fluid are necessary. Test resu… more
Date: November 20, 1978
Creator: Fleming, J R
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Heat exchanger method - ingot casting fixed abrasive method - multi-wire slicing. Phase II. Silicon sheet growth development for the Large Area Sheet Task of the Low Cost Solar Array Project. Quarterly progress report No. 4 for July 1--September 30, 1978

Description: Solar cells fabricated from HEM cast silicon have yielded up to 15% conversion efficiencies. This has been achieved in spite of using unpurified graphite parts in the HEM furnace and without optimization of material or cell processing parameters. Molybdenum retainers have prevented SiC formation and reduced carbon content by 50%. The oxygen content of vacuum cast HEM silicon is lower than typical Czochralski grown silicon. Impregnation of 45 ..mu..m diamonds into 7.5 ..mu..m copper sheath has s… more
Date: October 15, 1978
Creator: Schmid, F. & Khattak, C.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Phase 2 of the Array Automated Assembly Task for the Low Cost Silicon Solar Array Project. First quarterly report, October 1, 1977--December 31, 1977

Description: A process sequence is proposed and analyzed with regard to yield and cost of direct materials for fabrication. Cells of at least 13% conversion efficiency and panels of 10% efficiency have been assumed. Material costs, excluding silicon, were estimated as low as $0.19/watt (1975). Use of the JPL Interim Price Estimation Guidelines gives a projected contribution to selling price of $0.24/watt (1975) for the direct materials used in processing. If silicon is included, the contribution to selling … more
Date: April 26, 1978
Creator: Szedon, J. R.; Campbell, R. B.; Ghoshtagore, R. N. & Yoldas, B. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Heat exchanger method, ingot casting; fixed abrasive method, multi-wire slicing: Phase II. Silicon sheet growth development for the Large-Area Silicon Sheet Task of the Low-Cost Silicon Solar Array Project. Quarterly progress report No. 2, January 1, 1978--March 31, 1978

Description: A crack-free silicon ingot has been cast in a graded, semiconductor purity silica crucible. More than 90% single crystallinity has been achieved in 2.5 kg cast ingots. The impurities on the surface of the melt have been reduced with the use of a rapid heat-up cycle and absence of graphite retainers. Solar cells fabricated out of HEM cast material have shown conversion efficiency up to 14% under AM1 Xenon source illumination. Considerable progress has been achieved in casting square cross-sectio… more
Date: April 7, 1978
Creator: Schmid, F & Khattak, C P
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Phase 2 of the Array Automated Assembly Task for the Low Cost Silicon Solar Array Project. Second quarterly report, January 1--March 31, 1978

Description: Development effort has been applied in these areas during the second quarter: effects of back surface field (BSF) region diffusions, application of anti-reflection coatings and photoresist layers to web silicon cells by dipping and cell separation by laser scribing. In addition, consideration has been given to selecting appropriate adhesives for encapsulation of completed modules. A review has been made of the properties of several organic materials as candidates for the adhesives in preparing … more
Date: May 23, 1978
Creator: Szedon, J. R.; Campbell, R. B.; Ghoshtagore, R. N.; O'Keeffe, T. W. & Scala, L. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Assessment of present state-of-the-art sawing technology of large diameter ingots for solar sheet material. Final report, September 1, 1977-February 28, 1978

Description: The objective of this program is to assess the present state-of-the-art sawing technology of large diameter silicon ingots (3" and 4" diameter) for solar sheet materials. During this program, work has progressed in: (1) slicing of the ingots with the multiblade slurry (MBS) saw, the multiwire slurry (MWS) saw and the I.D. saw, (2) characterization of the sliced wafers, and (3) analysis of add-on slicing cost based on SAMICS. Multiblade slurry slicing resulted in mechanical wafer yields of 95% f… more
Date: January 1, 1978
Creator: Yoo, H.I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Multi-wire slurry wafering demonstrations

Description: A series of ten slicing demonstrations on a multi-wire slurry saw, manufactured by Yasunaga Engineering Company of Japan and distributed by GEOS Corporation of Stamford, Connecticut, was made to evaluate the silicon ingot wafering capabilities. The results revealed that the present sawing capabilities can provide usable wafer area from an ingot 1.05 m/sup 2//kg (e.g., kerf width 0.135 mm and wafer thickness 0.265 mm). Satisfactory surface qualities and excellent yield of silicon wafers were fou… more
Date: February 22, 1978
Creator: Chen, C. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Automated Array Assembly, Phase 2. Quarterly technical progress report, fourth quarter 1977. Texas Instruments report No. 03-77-56

Description: The Automated Array Assembly Task, Phase 2 of the Low Cost Silicon Solar Array (LSSA) Project, is a process development task. This contract includes solar cell module process development activities in the areas of Surface Preparation, Plasma Processing, Diffusion, Cell Processing and Module Fabrication. In addition, a High Efficiency Cell Development Activity is included. During this quarter, effort was concentrated on wafer etching for saw damage removal, establishing a standard phosphorous di… more
Date: January 1, 1978
Creator: Carbajal, Bernard G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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