µc-Si: H Thin Film Materials and Metastability Effects

Year 2017, Volume: 8 Issue: 1, 46 - 55, 29.03.2017

Gökhan Yılmaz

Abstract

Hydrogenated
Microcrystalline Silicon thin film materials (µc-Si:H) are much more preferable
material group than Single Crystalline Silicon (c-Si) and Hydrogenated
Amorphous Silicon (a-Si:H) due to their optoelectronic specification, easy and
cheap production techniques. New application areas of µc-Si:H have been
improved with concurrently production technology improvement. Diode, Sensors,
TFT, Photovoltaic and Heterojunction applications are examples of these
improvements. Depending on these production improvement, high quality µc-Si:H
can be produced. Therefore, these improvements draw attention of scientists
regarding production of high quality electrical materials and their application
areas. However; µc-Si:H materials have electronic metastability problems after
production. Researchers have been working on solving this metastability problem
of µc-Si:H for since 1983. Unfortunately, ultimate solution of metastability
problem for µc-Si:H material has not been revealed until now. Thus, in this
study, µc-Si:H thin films production, crystallographic structure, electronic
structure, optical and electrical specification of µc-Si:H thin film
chronologically have been analyzed through a detailed literature review and
findings have been investigated through the perspective of metastability
problem.

Keywords

µc-Si:H, a-Si:H, VHF-PECVD, Dark Conductivity, Photo Conductivity, Metastability

µc-Si:H İnce Film Malzemeler ve Metastabilite Etkileri

Abstract

Hidrojenlendirilmiş mikrokristal silisyum (µc-Si:H)
ince film malzemeler sahip oldukları optoelektronik özellikleri, üretim
sürecinin kolaylığı ve ucuzluğu açısından tek kristal silisyum (c-Si) ve
Hidrojenlendirilmiş amorf silisyuma (a-Si:H) göre daha çok tercih edilen bir
malzeme grubudur. Özellikle malzeme üretim teknolojilerinin gelişmesi ile µc-Si:H
ince film malzemelerin kullanım alanları da gelişmiş ve gelişmektedir. Diyot,
Sensör, TFT, Fotovoltaik ve Heteroeklem uygulamarı bu gelişmeye örneklerdir. Bu
gelişime bağlı olarak yüksek elektronik kalitede (State of Art) malzemelerin
üretilmesi ve uygulama alanları konusunda araştırmacıların dikkatini
çekmektedir. Ancak µc-Si:H ince film malzemeler üretim sonrası elektronik
olarak kararsızlık (metastabilite) problemi bulunmaktadır. Araştırmacılar
metastabilite probleminin 1983 yılında belirlenmesinden beri hala çözümü için
çalışıyorlar. Maalesef µc-Si:H ince film malzemelerin metastabilite problemi
için nihai bir çözümü günümüze kadar bulunamamıştır. Bu nedenle bu çalışmada µc-Si:H
ince film malzemenin üretimi, kristalografik yapısı, elektronik yapısı,
optiksel ve elektriksel özellikleri detaylı bir literatür araştırması ve
bulguları ile metastabilite problemi bakış açısından incelenmiştir.

Keywords

µc-Si:H, a-Si:H, VHF-PECVD, Karanlık Öziletkenlik, Foto Öziletkenlik

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