THIN-FILM TRANSISTOR AND MANUFACTURING METHOD THEREFOR

摘要

Provided is a back-channel etch type thin-film transistor (TFT) without an etch stopper layer, wherein an oxide semiconductor of the TFT has excellent resistance to an acid etchant and stress stability. The oxide semiconductor layer is a laminate having a first layer comprising tin, indium, and gallium or zinc, and oxygen, and a second layer comprising one or more elements selected from a group consisting indium, zinc, tin and gallium; and oxygen. The TFT is formed, in the following order, a gate insulator film, the second semiconductor layer and the first semiconductor layer; and having a value in a cross section in the lamination direction of the TFT, as determined by [100×(the first layer thickness of directly below a source-drain electrode end−a center portion thickness of the first layer)/the first layer thickness of directly below the source-drain electrode end], of not more than 5%.

主权项

1. A thin film transistor comprising;
a gate electrode, a gate insulator film, an oxide semiconductor layer, a source-drain electrode, and a passivation film to protect the source-drain electrode, on a substrate in this order, the oxide semiconductor layer is a laminate comprising: a first oxide semiconductor layer consisting of Sn; In; and at least one of Ga and Zn; and O; and a second oxide semiconductor layer consists of one or more kinds of element selected from the group consisting of In, Zn, Sn, and Ga; and O, wherein the second oxide semiconductor layer is formed on the gate insulator film; the first oxide semiconductor layer is formed between the second oxide semiconductor layer and the passivation film or between the second oxide semiconductor layer and the source-drain electrode; and a value in a cross section in the lamination direction of the thin film transistor, as determined by [100×(the thickness of the first oxide semiconductor layer directly below a source-drain electrode end−the thickness in the center portion of the first oxide semiconductor layer)/the thickness of the first semiconductor layer directly below the source drain electrode end] is equal to or smaller than 5%.