Impact of Hydrogen Dilution on the Properties and Light Induced Changes of A-SI:H Based Materials and Solar Cells

1997 ◽  
Vol 467 ◽  
Author(s):  
Yeeheng Lee ◽  
Lihong Jiao ◽  
Joohyun Koh ◽  
Hiroyuki Fujiwara ◽  
Zhou Lu ◽  
...  

ABSTRACTStudies have been carried out on a-Si:H materials and corresponding solar cells fabricated with and without hydrogen dilution of silane by rf PECVD. The effect of hydrogen dilution on the growth kinetics and microstructures and their dependence on the substrate temperature have been studied. Hydrogen diluted a-Si:H materials and solar cells exhibit improved properties and higher stability to light induced changes. Distinct differences are found in the electron mobility lifetime (μτ) products and subgap absorption over a wide range of generation rates. Striking differences are also found in the kinetics of light induced degradation in both the materials and their corresponding solar cells. Direct correlations are presented between the degradation kinetics of p(a-SiC:H)/i(a-Si:H)/n(μc-Si) solar cells and those of thin film materials constituting the i-layers.

2000 ◽  
Vol 609 ◽  
Author(s):  
Randy Koval ◽  
Xinwei Niu ◽  
Joshua Pearce ◽  
Lihong Jiao ◽  
Gautam Ganguly ◽  
...  

ABSTRACTStudies have been carried out on the kinetics of light induced changes in thin films and solar cells fabricated in different laboratories. Unlike the many studies on undiluted a-Si:H films the kinetics reported here are for 1 sun illuminations carried out to the degraded steady state (DSS). The light induced changes at temperatures from 25 to 100°C were characterized with electron mobility lifetime products and subgap absorption in films and fill factors in solar cells. The significant changes in the degradation kinetics that occur in these materials in this t mperature range have further confirmed the importance of charged defects, not only in the annealed state, but also in the degraded steady states. Results are also presented on corresponding solar cell structures, which also indicate that defects other than neutral dangling bonds have to be taken into account if any meaningful evaluation is to be made of their solar cell properties.


1994 ◽  
Vol 2 (3) ◽  
pp. 211-219 ◽  
Author(s):  
Masato Nishikuni ◽  
Tsuyoshi Takahama ◽  
Shingo Okamoto ◽  
Kunimoto Ninomiya ◽  
Hidenori Nishiwaki ◽  
...  

2011 ◽  
Vol 20 (3) ◽  
pp. 294-297 ◽  
Author(s):  
Taeho Moon ◽  
Jin Hyung Jun ◽  
Hyun Lee ◽  
Wonki Yoon ◽  
Soohyun Kim ◽  
...  

2000 ◽  
Vol 609 ◽  
Author(s):  
Yoshihiro Hamakawa

ABSTRACTA review is given on a research trajectory of amorphous and microcrystalline semiconductors and their device applications proceeded since 1970. A brief explanation on the motivation to start amorphous semiconductor research is given to produce a new kind of synthetic semiconductor having continuous energy gap controllability with valency electron controllability through our experience of modulation spectroscopy in semiconductors.The first material we have challenged is Si-As-Te chalcogenide semiconductor which has a very wide vitreous region in Gibb's Triangle. A series of systematic experiments has been carried out in the terrestrial environment since 1971, and also within the TT-500A rocket experiment in 1980, and the Spacelab. J experiments FMPT (First Material Processing Test) project in 1992. The second material is hydrogenated amorphous silicon (a-Si:H) and its alloys started in 1976 just after the Garmisch Partenkirchen ICALS-6. With some basic research on the a-Si:H film deposition technology and film quality improvement, our continuous effort to improve the efficiency bore the tandem type solar cells in 1979, and also new products of a-SiC:H and a-SiGe:H in the early period of 1980s are described. These innovative device structures and materials have bloomed in the middle of 1980s in R & D phase such as a-SiC/a-Si heterojunction solar cells, a-Si/a-SiGe and also a-Si/poly-Si tandem type solar cells, and industrialized in recent few years. New kind of trials on full-color thin film light emitting devices has also been recently initiated with wide range of band gap controllability of a-SiC:H.The third material is microcrystalline silicon (µc-Si) and their alloys which gathers a tremendous R & D effort as a promised candidate for the bottom cell of the a-Si/µc-Si tandem solar cells aimed for the all-round plasma CVD process for the next age thin film photovoltaic devices. In the final part of presentation, a brief discussion will be given on a technological evolution from “bulk crystalline age” to “multilayered thin film age” in the semiconductor optoelectronics toward 21 century.


2019 ◽  
Vol 966 ◽  
pp. 398-403
Author(s):  
Yoyok Cahyono ◽  
Novita Dwi Purnamasari ◽  
Mochamad Zainuri ◽  
Suminar Pratapa ◽  
Darminto

Effect of defect - through observation of energy absorption Urbach, on deposition rate, energy band gap, and surface roughness of intrinsic thin film are investigated using Radio Frequency Plasma Enhance Chemical Vapor Deposition (RF-PECVD). Films are grown on ITO (Indium Tin Oxide) glass substrate. Analysis of energy band gap is conducted to determine changes in the structure of a thin film of a-Si:H. Energy band gap is important to determine the portion of the spectrum of sunlight that is absorbed solar cells. From the characterization using UV-Vis spectrometer and the Tauc’s plot method, the width of the resulting energy band gap is greater if the hydrogen dilution is increased. It can be shown that the increase of the hydrogen dilution, will increase the energy band gap, and the surface roughness of thin layers. Instead, the improvement of the hydrogen dilution decrease the rate of deposition and Urbach energy. It is estimated that with greater hydrogen dilution, an intrinsic thin film of a-Si:H is more conductive for more reduction in residual of band tail defects or dangling bond defects.


2016 ◽  
Vol 2016 ◽  
pp. 1-8
Author(s):  
Pei-Ling Chen ◽  
Po-Wei Chen ◽  
Min-Wen Hsiao ◽  
Cheng-Hang Hsu ◽  
Chuang-Chuang Tsai

The enhancement of optical absorption of silicon thin-film solar cells by the p- and n-typeμc-SiOx:H as doped and functional layers was presented. The effects of deposition conditions and oxygen content on optical, electrical, and structural properties ofμc-SiOx:H films were also discussed. Regarding the dopedμc-SiOx:H films, the wide optical band gap (E04) of 2.33 eV while maintaining a high conductivity of 0.2 S/cm could be obtained with oxygen incorporation of 20 at.%. Compared to the conventionalμc-Si:H(p) as window layer inμc-Si:H single-junction solar cells, the application ofμc-SiOx:H(p) increased theVOCand led to a significant enhancement in the short-wavelength spectral response. Meanwhile, the employment ofμc-SiOx:H(n) instead of conventional ITO as back reflecting layer (BRL) enhanced the external quantum efficiency (EQE) ofμc-Si:H single-junction cell in the long-wavelength region, leading to a relative efficiency gain of 10%. Compared to the reference cell, the optimized a-Si:H/μc-Si:H tandem cell by applying p- and n-typeμc-SiOx:H films achieved aVOCof 1.37 V,JSCof 10.55 mA/cm2, FF of 73.67%, and efficiency of 10.51%, which was a relative enhancement of 16%.


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