wilson wenas - Academia.edu (original) (raw)

Papers by wilson wenas

Jurnal Fisika Indonesia, 2003

... SIFAT LISTRIK DAN OPTIK DARI LAPISAN TIPIS ZnO:B YANG DITUMBUHKAN DENGAN METODE METALORGANIC ... more ... SIFAT LISTRIK DAN OPTIK DARI LAPISAN TIPIS ZnO:B YANG DITUMBUHKAN DENGAN METODE METALORGANIC CHEMICAL VAPOR DEPOSITION Feri Adriyanto'1 dan Wilson W Wenas ' ^Lab. Fisika Material Jurusan Fìsika Universitas Sebelas Maret Jl. Ir. Sutami No. ...

DOAJ (DOAJ: Directory of Open Access Journals), 2019

... Wilson W. Wenas, A.Setiawan, F.Adriyanto and H. Sangian Semiconductor Research Laboratory, De... more ... Wilson W. Wenas, A.Setiawan, F.Adriyanto and H. Sangian Semiconductor Research Laboratory, Department of Physics Institute of Technology Bandung, JL. ... The crystal orientation of the films were evaluated by X-ray dieaction. ...

Polycrystalline ZnO films with various sizes and shapes of grain are required for their further a... more Polycrystalline ZnO films with various sizes and shapes of grain are required for their further applications as transparent conducting material in solar cell in order not only to scatter sunlight in wider wavelength range but also to avoid the shunting due to strongly rough surface morphology. In this study, two-step growth method of metalorganic chemical vapor deposition (MOCVD) process is proposed to modify the surface morphology of the films. In the proposed method, the film was grown in two steps successively. For the first layer, the tetrapodlike surface morphology of ZnO film with a [110] grain orientation was grown using the diethylzinc/H/sub 2/O reactant system at a substrate temperature of 150/spl deg/C. The film having smoother surface morphology with [002] and/or (100) grain orientations were then grown on the top of the first layer using diethylzinc/ethanol/H/sub 2/O reactant system. By varying the thickness of both layers, ZnO film with various shapes of textured and various grain sizes could be successfully deposited. B/sub 2/H/sub 6/ was also employed as n-type dopant gas for increasing the conductivity of the film. The obtained films are proper for being used as transparent conducting electrode.

Journal of Applied Physics, Dec 1, 1991

Globally, there is a high demand for clean, sustainable and renewable energy for domestic and ind... more Globally, there is a high demand for clean, sustainable and renewable energy for domestic and industrial use. Conventional photovoltaic cell technology relies heavily on crystalline silicon wafers which render silicon-based solar cells expensive due to the initial cost of production and required complex deposition methods. Due to these challenges, great research interest is now directed towards thin-film solar cells. In this work, the metal-organic chemical vapour deposition (CVD) method was chosen in the preparation of boron-doped zinc oxide (ZnO: B) thin film onto a glass slide substrate. The prepared ZnO: B thin films were characterized and optimized as a window

Japanese Journal of Applied Physics, Jul 1, 1991

We have grown high-conductivity textured ZnO films by the photo-MOCVD method using DEZ (diethylzi... more We have grown high-conductivity textured ZnO films by the photo-MOCVD method using DEZ (diethylzinc) and H2O as reactant gases. It was found that the UV light irradiation during the growth was very effective in the improvement of electron mobility. The improvement of the electron mobility could be caused by the chemisorption of the oxygen at the grain boundaries. The boron-doped ZnO films were also grown by photo-MOCVD using B2H6 as dopant gas. The resistivity of the films grown with UV irradiation was one order of magnitude less than that grown without UV irradiation, and the minimum resistivity of 6.8×10-4 Ω·cm was obtained by the photo-MOCVD method.

Japanese Journal of Applied Physics, Mar 1, 1991

Large-area ZnO films with high-transparency and high-conductivity were successfully grown on the ... more Large-area ZnO films with high-transparency and high-conductivity were successfully grown on the 10×10 cm2 substrates by the photo-MOCVD technique at a very low temperature of 135°C. The films have a good uniformity in thickness, resistivity and crystallinity with a deviation level of 5%. The obtained ZnO films were applied to a-Si solar cells as a TCO and a conversion efficiency

The growth of hydrogenated amorphous silicon (a-Si:H) and hydrogenated amorphous silicon nitride ... more The growth of hydrogenated amorphous silicon (a-Si:H) and hydrogenated amorphous silicon nitride (aSiN:H) films was studied by plasma enhanced chemical vapor deposition (PECVD) method. 10% silane (SiH4) diluted in'hydrogen (H,) gas and 100% ammonia (NH,) gas were used as gas sources. The optical band-gap and deposition rate of a-Si:H film were found varied from 1.70 to 1.95 eV and 5 1 to 84 Ao/min, respectidly, when the SiHl gas flow rate varied from 5 to 11 sccm. The widest optical bandgap of aSiN:H films whichis of 3.69 eV and lowest dark conductivity of 1.07~10-~' Scni-' were obtained at NH3 gas fraction of 60% at SiH, flow rate 7 sccm. It is also shown that wider optical bandgap of a-SiN:H can be obtained at the flow rate of SiH4 gas of 5 sccm where its value reaches 3.97 eV at NH3 gas fraction of 25%, whilst its dark conductivity reaches lower value of 1.05x10-12 Scm-I. The application of the films as an insulator gate in the thin film transistor (TFT) device was also studied. The lowest dark conductivity of the a-SiN:H film resulted in a better device thereshold voltage.

Textured ZnO films were grown by metalorganic chemical vapor deposition (MOCVD) using diethylzinc... more Textured ZnO films were grown by metalorganic chemical vapor deposition (MOCVD) using diethylzinc (DEZ) and H/sub 2/O as reactant gases. For the low-substrate temperature of 150 degrees C, the surface consists of uniformly sized tetrapod-like features. These undoped films have a high transparency in a wide wavelength range from 400 nm to 1400 nm. The B/sub 2/H/sub 6/ gas was also used as a n-type dopant gas to obtain highly conductive ZnO film with a resistivity of 2.4*10/sup -3/ Omega -cm. Furthermore, the obtained ZnO films were used to fabricate an a-Si solar cell, and a high conversion efficiency of 11.2% was obtained. A novel photoexcitation process (photo-MOCVD) was employed for the improvement of the film quality, and it was found that the ultraviolet (UV) light irradiation onto the substrate during the growth was very effective in improving the electron mobility.<<ETX>>

In this study special importance is attached to the ZnO/p and n/ZnO interfaces. a-Si solar cells ... more In this study special importance is attached to the ZnO/p and n/ZnO interfaces. a-Si solar cells with a structure of glass/ZnO/delta doped p/buffer/i/n/ZnO/Ag/Al have been fabricated. By optimizing the grain size of the films along with their electrical and optical properties, a high conversion efficiency of 12.5% was obtained under AM-1.5 illumination. The collection efficiency of the cell at 700 nm reached 60%. Furthermore, effects of interface states represented by a barrier En at the n/metal contact were investigated. It was found that this barrier affected the performance of the cells, particularly when the n-layer became thin. Finally, to demonstrate the electrical role of the ZnO at back contact, p-i-n a-Si solar cells having thin n-layer combined with ZnO back contact were fabricated. It was surprisingly found that the performance of the cells with ZnO at back contact did not deteriorate though the thickness of the n-layer was reduced to 3 nm

Japanese Journal of Applied Physics, Feb 1, 1993

Textured ZnO films with low resistivity and high transparency in a wide wavelength range from 400... more Textured ZnO films with low resistivity and high transparency in a wide wavelength range from 400 nm to 1400 nm have been successfully grown by the photo-induced metalorganic chemical vapor deposition (MOCVD) technique. It was found that ultraviolet irradiation during deposition was very effective in improving the electrical properties of the films, even with a low intensity. The obtained films have a good uniformity along the 10×10 cm2 substrate.

Journal of Mathematical and Fundamental Sciences, 2001

Abstract. Effect of B-doping B 2 H 6 on the crystal structural and optical properties of zinc oxi... more Abstract. Effect of B-doping B 2 H 6 on the crystal structural and optical properties of zinc oxide (ZnO) thin films has been studied. The crystal orientation of these films were evaluated by X-ray diffraction. It was found that the (110) reflection peak was dominant for all the film and became less pronounced as B 2 H 6 flow rate was increased. The grain size of thin film decreased as B 2 H 6 flow rate was increased. The transmittance in the ultraviolet wavelengths region shifted to higher energy as the B 2 H 6 flow rate was increased. I t was also found that refractive index of ZnO thin films increased as the B 2 H 6 flow rate was further increased. These doping effects should be minimized in order to grow low resistivity ZnO film with excellent optical properties for application to photonic devices. Efek Doping Boron (B) terhadap Struktur Kristal dan Sifat Optik Lapisan Tipis ZnO untuk Divais Optoelektronik Sari. Telah dilakukan studi tentang pengaruh doping B 2 H 6 terhadap s...

Dalam studi ini dikaji sifat-sifat struktur double barrier pada divais silikon amorf (a-Si). Stru... more Dalam studi ini dikaji sifat-sifat struktur double barrier pada divais silikon amorf (a-Si). Struktur double barrier dibangun dengan mengkombinasikan material a-Si:H dengan material a-SiC:H yang memiliki celah energi optik yang berbeda. Material a-Si:H berfungsi sebagai sumur kuantum di antara material a-SiC:H yang berfungsi sebagai barrier. Probabilitas tunneling yang menjadi pokok utama sifat-sifat struktur double barrier dihitung berdasarkan persamaan Schroedinger, pendekatan WKB, dan pendekatan Lorentzian. Probabilitas tunneling mencapai harga 0,12 untuk tegangan luar 10 V, tebal barrier 10 A dan lebar sumur potensial 10 A. Selanjutnya, hasil perhitungan probabilitas tunneling diaplikasikan pada salah satu divais a-Si yaitu Thin Film Light Emitting Diode (TFLED), untuk menghitung rapat arus tunneling dan brightness. Didapatkan bahwa semakin tinggi probabilitas tunneling, rapat arus tunneling semakin meningkat dan pada akhirnya dapat meningkatkan harga brightness dari TFLED.

1998 Conference on Optoelectronic and Microelectronic Materials and Devices. Proceedings (Cat. No.98EX140)

ICSE 2000. 2000 IEEE International Conference on Semiconductor Electronics. Proceedings (Cat. No.00EX425)

The growth of hydrogenated amorphous silicon (a-Si:H) and hydrogenated amorphous silicon nitride ... more The growth of hydrogenated amorphous silicon (a-Si:H) and hydrogenated amorphous silicon nitride (a-SiN:H) films was studied by plasma enhanced chemical vapor deposition (PECVD) method. 10% silane (SiH4) diluted in'hydrogen (H,) gas and 100% ammonia (NH,) gas were used as gas sources. The optical band-gap and deposition rate of a-Si:H film were found varied from 1.70 to 1.95 eV and 5 1 to 84 Ao/min, respectidly, when the SiHl gas flow rate varied from 5 to 11 sccm. The widest optical bandgap of a-SiN:H films whichis of 3.69 eV and lowest dark conductivity of 1. 0 7~1 0-~' Scni-' were obtained at NH3 gas fraction of 60% at SiH, flow rate 7 sccm. It is also shown that wider optical bandgap of a-SiN:H can be obtained at the flow rate of SiH4 gas of 5 sccm where its value reaches 3.97 eV at NH3 gas fraction of 25%, whilst its dark conductivity reaches lower value of 1.05x10-12 Scm-I. The application of the films as an insulator gate in the thin film transistor (TFT) device was also studied. The lowest dark conductivity of the a-SiN:H film resulted in a better device thereshold voltage.

Japanese Journal of Applied Physics, 1978

Jurnal Fisika Indonesia, 2003

DOAJ (DOAJ: Directory of Open Access Journals), 2019

Journal of Applied Physics, Dec 1, 1991

Japanese Journal of Applied Physics, Jul 1, 1991

Japanese Journal of Applied Physics, Mar 1, 1991

Japanese Journal of Applied Physics, Feb 1, 1993

Journal of Mathematical and Fundamental Sciences, 2001

1998 Conference on Optoelectronic and Microelectronic Materials and Devices. Proceedings (Cat. No.98EX140)

ICSE 2000. 2000 IEEE International Conference on Semiconductor Electronics. Proceedings (Cat. No.00EX425)

The growth of hydrogenated amorphous silicon (a-Si:H) and hydrogenated amorphous silicon nitride ... more The growth of hydrogenated amorphous silicon (a-Si:H) and hydrogenated amorphous silicon nitride (a-SiN:H) films was studied by plasma enhanced chemical vapor deposition (PECVD) method. 10% silane (SiH4) diluted in'hydrogen (H,) gas and 100% ammonia (NH,) gas were used as gas sources. The optical band-gap and deposition rate of a-Si:H film were found varied from 1.70 to 1.95 eV and 5 1 to 84 Ao/min, respectidly, when the SiHl gas flow rate varied from 5 to 11 sccm. The widest optical bandgap of a-SiN:H films whichis of 3.69 eV and lowest dark conductivity of 1. 0 7~1 0-~' Scni-' were obtained at NH3 gas fraction of 60% at SiH, flow rate 7 sccm. It is also shown that wider optical bandgap of a-SiN:H can be obtained at the flow rate of SiH4 gas of 5 sccm where its value reaches 3.97 eV at NH3 gas fraction of 25%, whilst its dark conductivity reaches lower value of 1.05x10-12 Scm-I. The application of the films as an insulator gate in the thin film transistor (TFT) device was also studied. The lowest dark conductivity of the a-SiN:H film resulted in a better device thereshold voltage.

Japanese Journal of Applied Physics, 1978