Fabrication of BaSi2 homojunction diodes on Nb-doped TiO2 coated glass substrates by aluminum-induced crystallization and two-step evaporation method

Abstract BaSi2 homojunction diodes on Nb-doped TiO2 (TiO2:Nb) coated glass substrates were fabricated using aluminum-induced crystallization (AIC) and two-step evaporation method. From Raman scattering spectra, the growth of BaSi2 on TiO2:Nb was confirmed when the thickness of poly-Si grown by AIC (AIC-Si) was more than 150 nm. The partial formation of BaSi2 diodes was confirmed from the samples prepared at temperature during AIC TAIC=475-525 oC. The long-wavelength edge of photoresponsivity of the diodes was located around 950 nm, which corresponds to the bandgap of BaSi2 of 1.3 eV, suggesting that this photocurrent is derived from BaSi2 thin films. At TAIC =500 oC, the maximum value of photoresponsivity was obtained. Since the largest grains in AIC-Si were also obtained at TAIC=500 oC, these results suggest that larger grain of AIC-Si leads to the improvement of the quality of BaSi2 thin films themselves and the performance of BaSi2 diodes.

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Al-induced crystallization of amorphous Ge thin films on conducting layer coated glass substrates

Japanese Journal of Applied Physics ◽

10.7567/jjap.53.04eh01 ◽

2014 ◽

Vol 53 (4S) ◽

pp. 04EH01 ◽

Cited By ~ 5

Author(s):

Koki Nakazawa ◽

Kaoru Toko ◽

Noritaka Usami ◽

Takashi Suemasu

Keyword(s):

Thin Films ◽

Conducting Layer ◽

Coated Glass ◽

Glass Substrates ◽

Induced Crystallization

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Preparation of high quality polycrystalline silicon thin films by aluminum induced crystallization

Science and Technology Development Journal ◽

10.32508/stdj.v16i1.1419 ◽

2013 ◽

Vol 16 (1) ◽

pp. 57-63

Author(s):

Tu Linh Phan ◽

Duy Phong Pham ◽

Bach Thang Phan ◽

Cao Vinh Tran

Keyword(s):

Thin Films ◽

Polycrystalline Silicon ◽

Thickness Ratio ◽

Vacuum Furnace ◽

High Quality ◽

Sem Images ◽

Transmission Microscopy ◽

Glass Substrates ◽

Induced Crystallization ◽

Aluminum Induced Crystallization

In this paper, high-quality polycrystalline silicon (poly-Si) thin films on glass substrates are formed by Aluminum-induced crystallization (AIC). In AIC processes, bi-layer structures of amorphous silicon (a-Si) / Al are transformed into ones of (Al+ residual Si)/ poly-Si after simply annealing at 500°C in vacuum furnace. After Al chemical etchings, it isobserved that the obtained structures are poly-Si thinfilms on glasses with some amount of residual Si as“ islands”scattered on theirsurfaces. The number of these “Si islands” remarkedly reduced by choosing an appropriate thickness ratio of pre-annealled Al and Si layers that prepared by magnetron dc sputtering. In this study, at initial Al/a-Si thickness ratio of 110/230 nm, the high-quality poly-Si thin films are formed with very few“Si islands” on the surfaces after AIC processes. Theobtained smooth surfaces are not appearing “dendritic” in optical transmission microscopy (OTM ) images, have large grain size of tens of nanometers in SEM images and have average surface roughness of about 2.8 nm in AFM images. In addition, XRD Ө -2Ө measurements show a strong Si (111) peak at the 2Ө angle of 28.5°, presenting good crystalline phases. The films also reveal good p-type electrical conductivityin that their high carrier concentration and mobility in Hall effect measurements are 1018 cm-3 and 48 cm2/Vs, respectively.

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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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Al-induced Crystallization of Amorphous-Ge Thin Films on Conducting Layer Coated Glass Substrates

10.7567/ssdm.2013.p-2-6 ◽

2013 ◽

Author(s):

K. Nakazawa ◽

K. Toko ◽

N. Usami ◽

T. Suemasu

Keyword(s):

Thin Films ◽

Conducting Layer ◽

Coated Glass ◽

Glass Substrates ◽

Induced Crystallization

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Layer exchange during aluminum-induced crystallization of silicon suboxide thin films

Materials Letters ◽

10.1016/j.matlet.2021.129723 ◽

2021 ◽

pp. 129723

Author(s):

A.O. Zamchiy ◽

E.A. Baranov ◽

I.E. Merkulova ◽

I.V. Korolkov ◽

V.I. Vdovin ◽

...

Keyword(s):

Thin Films ◽

Silicon Suboxide ◽

Induced Crystallization ◽

Aluminum Induced Crystallization

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Polycrystalline silicon thin films by aluminum induced crystallization of amorphous silicon

Applied Surface Science ◽

10.1016/j.apsusc.2012.09.019 ◽

2013 ◽

Vol 264 ◽

pp. 11-16 ◽

Cited By ~ 19

Author(s):

T. Wang ◽

H. Yan ◽

M. Zhang ◽

X. Song ◽

Q. Pan ◽

...

Keyword(s):

Thin Films ◽

Amorphous Silicon ◽

Polycrystalline Silicon ◽

Silicon Thin Films ◽

Induced Crystallization ◽

Aluminum Induced Crystallization

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Crystallization of Amorphous Silicon Thin Films by Microwave Heating

MRS Proceedings ◽

10.1557/opl.2014.920 ◽

2014 ◽

Vol 1666 ◽

Cited By ~ 1

Author(s):

Tomohiko Nakamura ◽

Shinya Yoshidomi ◽

Masahiko Hasumi ◽

Toshiyuki Sameshima ◽

Tomohisa Mizuno

Keyword(s):

Thin Films ◽

Heat Treatment ◽

Amorphous Silicon ◽

Microwave Heating ◽

Volume Ratio ◽

Heated Sample ◽

Silicon Thin Films ◽

Scattering Spectra ◽

Raman Scattering Spectra ◽

Si Films

ABSTRACTWe report crystallization of amorphous silicon (a-Si) thin films and improvement of thin film transistors (TFTs) characteristics using 2.45 GHz microwave heating assisted with carbon powders. Undoped 50-nm-thick a-Si films were formed on quartz substrates and heated by microwave irradiation for 2, 3, and 4 min. Raman scattering spectra revealed that the crystalline volume ratio increased to 0.42 for the 4-min heated sample. The dark and photo electrical conductivities measured by Air mass 1.5 at 100 mW/cm2 were 2.6x10-6 and 5.2x10-6 S/cm in the case of 4-min microwave heating followed by 1.3x106-Pa-H2O vapor heat treatment at 260°C for 3 h. N channel polycrystalline silicon TFTs characteristics were improved by the combination of microwave heating with high-pressure H2O vapor heat treatment. The threshold voltage decreased from 5.3 to 4.2 V and the effective carrier mobility increased from 18 to 25 cm2/Vs.

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