Polycrystalline thin-film transistors fabricated on high-mobility solid-phase-crystallized Ge on glass

K. Moto, Keisuke Yamamoto, T. Imajo, T. Suemasu, H. Nakashima, K. Toko

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Low-temperature formation of Ge thin-film transistors (TFTs) on insulators has been widely investigated to improve the performance of Si large-scale integrated circuits and mobile terminals. Here, we studied the relationship between the electrical properties of polycrystalline Ge and its TFT performance using high-mobility Ge formed on glass using our recently developed solid-phase crystallization technique. The field-effect mobility μFE and on/off currents of the accumulation-mode TFTs directly reflected the Hall hole mobility μHall, hole concentration, and film thickness of Ge. By thinning the 100-nm thick Ge layer with a large grain size (3.7 μm), we achieved a high μHall (190 cm2/Vs) in a 55-nm thick film that was almost thin enough to fully deplete the channel. The TFT using this Ge layer exhibited both high μFE (170 cm2/Vs) and on/off current ratios (∼102). This is the highest μFE among low-temperature (<500 °C) polycrystalline Ge TFTs without minimizing the channel region (<1 μm).

Original languageEnglish
Article number212107
JournalApplied Physics Letters
Volume114
Issue number21
DOIs
Publication statusPublished - May 27 2019

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solid phases
transistors
glass
thin films
hole mobility
thick films
integrated circuits
film thickness
grain size
electrical properties
insulators
crystallization

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)

Cite this

Polycrystalline thin-film transistors fabricated on high-mobility solid-phase-crystallized Ge on glass. / Moto, K.; Yamamoto, Keisuke; Imajo, T.; Suemasu, T.; Nakashima, H.; Toko, K.

In: Applied Physics Letters, Vol. 114, No. 21, 212107, 27.05.2019.

Research output: Contribution to journalArticle

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