µc-Si: H Thin Film Materials and Metastability Effects

Öz

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.

Anahtar Kelimeler

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

µc-Si:H İnce Film Malzemeler ve Metastabilite Etkileri

Öz

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.

Anahtar Kelimeler

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

Kaynakça

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