TFTs With High Overlay Alignment for Integration of Flexible Display Backplanes

Author

Moradi, Maryam ; Pathirane, Minoli ; Sazonov, Andrei ; Chaji, Reza ; Nathan, Arokia

Author_Institution

Ignis Innovation Inc., Kitchener, ON, Canada

Volume

8

Issue

2

fYear

2012

Firstpage

104

Lastpage

107

Abstract

Abstract-This work reports an integration process for hydrogenated amorphous silicon (a-Si:H) thin-film transistor (TFT) backplanes on flexible plastic substrates that attempts to reduce the large misalignment between the successive patterned layers in fabrication. Here, a double-sided adhesive tape is used to attach the plastic substrate to a rigid carrier. The results indicate a reduction of overlay misalignment from 22 μm on free-standing foil to 2 μm when laminated to a rigid carrier for five consecutive mask layers. Electrical characteristics of the fabricated a-Si:H TFTs on 3" round plastic substrates show an ON/OFF current ratio of over 10⁸, field-effect mobility of 0.8 cm²/V · s, and gate leakage current of 10^-13 A.

Keywords

adhesives; amorphous semiconductors; carrier mobility; elemental semiconductors; flexible displays; hydrogen; leakage currents; masks; silicon; thin film transistors; ON-OFF current ratio; Si:H; TFT; double-sided adhesive tape; electrical characteristics; field-effect mobility; flexible display backplane; flexible plastic substrate; free-standing foil; gate leakage current; high overlay alignment; hydrogenated amorphous silicon thin-film transistor; mask layer; successive patterned layer; Educational institutions; Fabrication; Lamination; Plastics; Substrates; Thin film transistors; Amorphous-silicon (a-Si:H); flexible backplanes; overlay misalignment; plastic substrate; thin-film transistors (TFTs);

fLanguage

English

Journal_Title

Display Technology, Journal of

Publisher

ieee

ISSN

1551-319X

Type

jour

DOI

10.1109/JDT.2011.2164894

Filename

6145185