Sequential purification and crystal growth for the production of low cost silicon substrates. Annual report, 15 September 1979-14 September 1980

Integration of highly anisotropic multiferroic thin films on silicon substrates is a critical step towards low-cost devices, especially high-speed and low-power consumption memories.

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Effectiveness of selective area growth using van der Waals h-BN layer for crack-free transfer of large-size III-N devices onto arbitrary substrates

Scientific Reports ◽

10.1038/s41598-020-77681-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Soufiane Karrakchou ◽

Suresh Sundaram ◽

Taha Ayari ◽

Adama Mballo ◽

Phuong Vuong ◽

...

Keyword(s):

Low Cost ◽

Van Der Waals ◽

Thermal Dissipation ◽

Silicon Substrates ◽

Device Performance ◽

Selective Area Growth ◽

Material Quality ◽

Large Size ◽

Selective Area ◽

Area Growth

AbstractSelective Area van der Waals Epitaxy (SAVWE) of III-Nitride device has been proposed recently by our group as an enabling solution for h-BN-based device transfer. By using a patterned dielectric mask with openings slightly larger than device sizes, pick-and-place of discrete LEDs onto flexible substrates was achieved. A more detailed study is needed to understand the effect of this selective area growth on material quality, device performance and device transfer. Here we present a study performed on two types of LEDs (those grown on h-BN on patterned and unpatterned sapphire) from the epitaxial growth to device performance and thermal dissipation measurements before and after transfer. Millimeter-size LEDs were transferred to aluminum tape and to silicon substrates by van der Waals liquid capillary bonding. It is shown that patterned samples lead to a better material quality as well as improved electrical and optical device performances. In addition, patterned structures allowed for a much better transfer yield to silicon substrates than unpatterned structures. We demonstrate that SAVWE, combined with either transfer processes to soft or rigid substrates, offers an efficient, robust and low-cost heterogenous integration capability of large-size devices to silicon for photonic and electronic applications.

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Fabrication of Polycrystalline Si Thin Film for Solar Cells

MRS Proceedings ◽

10.1557/proc-452-965 ◽

1996 ◽

Vol 452 ◽

Cited By ~ 3

Author(s):

M. Tanaka ◽

S. Tsuge ◽

S. Kiyama ◽

S. Tsuda ◽

S. Nakano

Keyword(s):

Thin Film ◽

Solar Cells ◽

Crystal Growth ◽

Conversion Efficiency ◽

Solid Phase ◽

Low Cost ◽

Back Surface ◽

Nucleation Layer ◽

Surface Reflection ◽

Si Thin Film

AbstractThe a-Si/poly-Si thin film tandem solar cell is a promising candidate for low-cost solar cells. We have conducted R&D on poly-Si thin film using the Solid Phase Crystallization (SPC) method from amorphous silicon (a-Si). To improve the film quality of SPC poly-Si, we have developed a new SPC method called the partial doping method. This method features two stacked starting a-Si layers, a P-doped layer and a non-doped layer. Nucleation occurs in the P-doped layer, and the non-doped layer is the crystal growth layer. For the nucleation layer, we developed a Si film with a unique structure, which features relatively large crystallites (-1000A) embedded in a matrix of amorphous tissue. By combining these technologies, a conversion efficiency of 9.2% was obtained for poly-Si thin-film solar cells. For further improvement in the conversion efficiency, based on the concept of “independent control of nucleation and crystal growth”, it is necessary to combine the best fabrication methods for each layer. A high conversion efficiency of more than 12% was found possible by using the CVD method and a new back surface reflection structure.

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The Fluids Experiment Apparatus (fea) and Rockwell's Industrial Space Processing Research Program

MRS Proceedings ◽

10.1557/proc-87-29 ◽

1986 ◽

Vol 87 ◽

Author(s):

Michael J. Martin

Keyword(s):

Crystal Growth ◽

Space Shuttle ◽

Low Cost ◽

Space Environment ◽

Advanced Materials ◽

Materials Processing ◽

Scientific Investigations ◽

Industrial Utilization ◽

Space Processing ◽

Experiment Hardware

AbstractRockwell International has long endeavored to stimulate industrial utilization of space for materials processing. A successful introductory briefing program to acquaint nonaerospace industry with the space environment, microgravity process phenomena, experiment hardware, and the programs available to conduct research in space has encouraged several companies to initiate space processing research projects.To help satisfy industry's microgravity experiment hardware requirements, Rockwell has developed a multipurpose materials processing laboratory for use on the Space Shuttle. The Fluids Experiment Apparatus (FEA) has been flown to perform floating zone crystal growth and purification research and is currently being used to support further crystal growth research with advanced materials for Rockwell. Other companies are preparing experiments that are expected to be conducted in the FEA on future Space Shuttle missions.Rockwell is developing, with NASA, a program that will allow industry to plan and fly microgravity materials processing experiments within a few months–much faster than the current one to two year lead time. This low-cost program, patterned after the NASA Joint Endeavor Program, provides Space Shuttle flight services and use ot the FEA to conduct scientific investigations. Rockwell plans to offer experiment integration and support services to industry as needed.

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