Passivation kinetics of two types of defects in polysilicon TFT by plasma hydrogenation

Author

Wu, I-Wei ; Huang, Tiao-Yuan ; Jackson, Warren B. ; Lewis, Alan G. ; Chiang, Anne

Author_Institution

Xerox Palo Alto Res. Center, CA, USA

Volume

12

Issue

4

fYear

1991

fDate

4/1/1991 12:00:00 AM

Firstpage

181

Lastpage

183

Abstract

The effects and kinetics of hydrogen passivation on polycrystalline-silicon thin-film transistors (poly-TFTs) are investigated. Based on the response of device parameters with the progress of hydrogenation, two types of defects can be distinguished from the difference in passivation rate. The threshold voltage and subthreshold slope, which are strongly influenced by the density of dangling bond midgap states, have a faster response to hydrogenation. The off-state leakage current and field-effect mobility, related to stain-bond tail states, respond more slowly to hydrogenation, with an onset period of approximately 4 to 12 h depending on the grain size. Since the larger-grain-size samples showed a longer onset period, the contribution of intragranular defects to the strain-bond tail states appears to be significant.<>

Keywords

carrier mobility; elemental semiconductors; passivation; silicon; thin film transistors; dangling bond midgap states; device parameters; field-effect mobility; intragranular defects; off-state leakage current; onset period; passivation rate; polysilicon TFT by plasma hydrogenation; subthreshold slope; threshold voltage; Grain size; Hydrogen; Kinetic theory; Passivation; Plasma devices; Semiconductor films; Senior members; Tail; Thin film transistors; Threshold voltage;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/55.75757

Filename

75757