Light trapping and reflection control for silicon thin films deposited on glass substrates textured by embossing

ABSTRACTWe analyze the formation kinetics and microstructure of hydrogenated vs. deuterated microcrystalline (μc-Si:H or D) thin films using real-time spectroscopic ellipsometry, post- deposition thermal hydrogen evolution, and TEM. The films are deposited by reactive magnetron sputtering of a silicon target in Ar (1.65 mT) with added partial pressures of H2or D2(0-5.5mT) on Coming 7059 glass substrates at 230°C. Amorphous films are deposited when PH2=0. When hydrogen is added to the chamber, the reactive magnetron sputtering process generates a flux of fast neutral H which promotes stc-Si growth. The substitution of D for H varies the kinetics of hydrogen reflection from the target and implantation into the growing film. We analyze the amorphous to microcrystalline transition as a function of the isotope (H2or D2) and pressure used in the deposition process. We find that the films enter the microcrystalline regime at lower D2pressures than H2pressures. Furthermore, the <ε2> data determined by ellipsometry have a different shape for deuterated films, compared to hydrogenated films at similar growth pressures. This indicates changes in band structure which we interpret as evidence for enhanced crystallinity.

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Characteristics of Bottom Gate Thin Film Transistors with Silicon rich poly-Si1-xGex and poly-Si fabricated by Reactive Thermal Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-762-a20.5 ◽

2003 ◽

Vol 762 ◽

Cited By ~ 1

Author(s):

Kousaku Shimizu ◽

JianJun Zhang ◽

Jeong-Woo Lee ◽

Jun-ichi Hanna

Keyword(s):

Thin Film ◽

Thin Films ◽

Thin Film Transistors ◽

High Mobility ◽

Chemical Vapor ◽

Hydrogen Treatment ◽

Glass Substrates ◽

Silicon Thin Films ◽

High Benefit ◽

Bottom Gate

AbstractIn the fabrication of thin film transistors (TFTs), little attention has been paid to the polycrystalline silicon thin films prepared at low temperatures where the glass substrates are adopted so far. Since the film quality is not sufficient to achieve high mobility, e.g., over 50 cm2/Vs in spite of high benefit in their industrial fabrication. We have fabricated bottom gate TFTs with poly-Si and poly- Si1-xGex thin films deposited at 450°C by newly developed low-temperature LPCVD technique and characterized electrical characteristics of the TFTs: disilane and a small amount of either germanium tetrafluoride or fluorine were used as material gases and helium as carrier gas. Thermal annealing for dopant activation and atomic hydrogen treatment for defect passivation were carried out. We found that the defect elimination process is important for improving TFT performance significantly. Finally the mobility of p-channel and n-channel TFTs have attained 36.3-54.4 cm2/Vs and 57 cm2/Vs, respectively.

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Multi crystalline silicon thin films grown directly on low cost soda-lime glass substrates

Solar Energy Materials and Solar Cells ◽

10.1016/j.solmat.2019.110168 ◽

2019 ◽

Vol 203 ◽

pp. 110168 ◽

Cited By ~ 4

Author(s):

Sven Kühnapfel ◽

Stefanie Severin ◽

Norbert Kersten ◽

Paul Harten ◽

Bert Stegemann ◽

...

Keyword(s):

Thin Films ◽

Crystalline Silicon ◽

Low Cost ◽

Soda Lime ◽

Soda Lime Glass ◽

Glass Substrates ◽

Silicon Thin Films

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Silicon Nanowire Solar Cells With Radial p-n Heterojunction on Crystalline Silicon Thin Films: Light Trapping Properties

IEEE Journal of Photovoltaics ◽

10.1109/jphotov.2013.2289873 ◽

2014 ◽

Vol 4 (1) ◽

pp. 28-32 ◽

Cited By ~ 18

Author(s):

Guobin Jia ◽

Annett Gawlik ◽

Joachim Bergmann ◽

Bjorn Eisenhawer ◽

Sven Schonherr ◽

...

Keyword(s):

Thin Films ◽

Solar Cells ◽

Crystalline Silicon ◽

Light Trapping ◽

Silicon Nanowire ◽

Silicon Thin Films

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Activation of ion-implanted polycrystalline silicon thin films prepared on glass substrates

Materials Research Bulletin ◽

10.1016/j.materresbull.2012.04.130 ◽

2012 ◽

Vol 47 (10) ◽

pp. 3048-3051 ◽

Cited By ~ 1

Author(s):

Byoung-Soo So ◽

Seung-Muk Bae ◽

Yil-Hwan You ◽

Young-Hwan Kim ◽

Jin-Ha Hwang

Keyword(s):

Thin Films ◽

Polycrystalline Silicon ◽

Glass Substrates ◽

Silicon Thin Films ◽

Ion Implanted

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Experimental Demonstration of Quasi-resonant Absorption in Silicon Thin Films for Enhanced Solar Light Trapping

ACS Photonics ◽

10.1021/ph400140f ◽

2014 ◽

Vol 1 (4) ◽

pp. 304-309 ◽

Cited By ~ 16

Author(s):

Ardavan Oskooi ◽

Menaka De Zoysa ◽

Kenji Ishizaki ◽

Susumu Noda

Keyword(s):

Thin Films ◽

Light Trapping ◽

Resonant Absorption ◽

Solar Light ◽

Experimental Demonstration ◽

Silicon Thin Films

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POLY-SILICON THIN FILMS PREPARED BY LOW TEMPERATURE ALUMINUM-INDUCED CRYSTALLIZATION

Modern Physics Letters B ◽

10.1142/s0217984901002373 ◽

2001 ◽

Vol 15 (17n19) ◽

pp. 716-721

Author(s):

YASUHIRO MATSUMOTO ◽

MASAO TAMURA ◽

RENE ASOMOZA ◽

ZHENRUI YU

Keyword(s):

Thin Films ◽

Low Temperature ◽

Glass Substrates ◽

Silicon Thin Films ◽

Boron Doped ◽

Hall Effect Measurements ◽

High Carrier ◽

P Type ◽

Induced Crystallization ◽

Aluminum Induced Crystallization

P-type poly-Si thin films prepared by low temperature Aluminum-induced crystallization and doping are reported. The starting material was boron-doped a-Si:H prepared by PECVD on glass substrates. Aluminum layers with different thicknessess were evaporated on a-Si:H surface and conventional thermal annealing was performed at temperatures ranging from 300 to 550°C. XRD, SIMS, TEM and Hall effect measurements were carried out to characterize the annealed films. Results show that a-Si:H contacted with adequate Al could be crystallized at temperature as low as 300°C after annealing for 60 minutes. This material has high carrier concentration as well as high Hall mobility can be used as a p-layer or seed layer for thin film poly-Si solar cells. The technique reported here is compatible with PECVD process.

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