Polysilicon TFT structures for kink-effect suppression

Author

Mariucci, L. ; Fortunato, G. ; Bonfiglietti, A. ; Cuscuná, M. ; Pecora, A. ; Valletta, A.

Author_Institution

Inst. di Fotonica & Nanotecnologie-CNR, Rome, Italy

Volume

51

Issue

7

fYear

2004

fDate

7/1/2004 12:00:00 AM

Firstpage

1135

Lastpage

1142

Abstract

Experimental results and numerical simulations of asymmetric fingered polysilicon thin-film transistors (AF-TFTs) are analyzed in detail. In the AF-TFTs, the transistor channel region is split into two zones with different lengths separated by a floating n⁺ region. This structure allows an effective reduction of the kink effect depending on the relative length of the two subchannels, without introducing any additional series resistance. In addition, an appreciable reduction of the leakage current is also observed. The AF-TFTs characteristics have been analyzed by two-dimensional numerical simulation and by modeling the device with two transistors in series. This model clarifies the mechanisms of kink effect suppression in AF-TFT. On the basis of this analysis, two new modified device structures for kink-effect suppression are also proposed and discussed.

Keywords

SPICE; capacitance measurement; chemical vapour deposition; circuit CAD; integrated circuit design; integrated circuit interconnections; 100 nm; SPICE; aluminum metal lines; aluminum/TEOS process; backend processes; backend simulations; capacitance extraction; charge-based capacitance measurements; chemical mechanical planarization; chemical vapor deposition; computer-aided design; dry etching; flat wafer surface; integrated circuit design; integrated circuit interconnections; interconnect capacitances; level-set method; line width; line-to-line space; metal combination; scanning electron microscope; time delays; titanium nitride local interconnects; topography simulation; Active matrix liquid crystal displays; Active matrix organic light emitting diodes; Circuits; Electric variables; Helium; Leakage current; Numerical simulation; Plasma temperature; Silicon; Thin film transistors; Kink-effect; TFTs; leakage current; polycrystalline silicon; thin-film transistors;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/TED.2004.829860

Filename

1308638