Thin film transistor manufacturing method, thin film transistor, thin film transistor substrate and image display apparatus, image display apparatus and semiconductor device
First Claim
1. A method for producing a thin film transistor comprising the steps of:
- a film-forming step in which an amorphous oxide film is formed as a channel layer;
a patterning step in which said amorphous oxide film is patterned by etching; and
a crystallization step in which said amorphous oxide film which is patterned in the patterning step is crystallized, resulting in the amorphous oxide film being converted to a crystalline oxide semiconductor film,wherein said crystallized crystalline oxide semiconductor film is provides a channel layer;
said crystalline oxide semiconductor film contains In and a positive divalent element;
said positive divalent element is one or more elements selected from Zn, Mg, Cu, Co, Ni and Ca; and
an atomic ratio of the In [In] and the positive divalent element [X] by the formula [X]/([X]+[In]) is such that 0.0001≦
[X]/([X]+[In])≦
0.5.
1 Assignment
0 Petitions
Accused Products
Abstract
To provide a method for producing a thin film transistor improved in stability, uniformity, reproducibility, heat resistance, durability or the like, a thin film transistor, a thin film transistor substrate, an image display apparatus, an image display apparatus and a semiconductor device.
In the semiconductor device, a crystalline oxide is used as an N-type transistor and the electron carrier concentration of the crystalline oxide is less than 2×1017/cm3. Furthermore, the crystalline oxide is a polycrystalline oxide containing In and one or more positive divalent elements selected from Zn, Mg, Cu, Ni, Co and Ca, and the atomic ratio In [In] and the positive divalent element [X][X]/([X]+[In]) is 0.0001 to 0.13.
-
Citations
32 Claims
-
1. A method for producing a thin film transistor comprising the steps of:
- a film-forming step in which an amorphous oxide film is formed as a channel layer;
a patterning step in which said amorphous oxide film is patterned by etching; and
a crystallization step in which said amorphous oxide film which is patterned in the patterning step is crystallized, resulting in the amorphous oxide film being converted to a crystalline oxide semiconductor film,wherein said crystallized crystalline oxide semiconductor film is provides a channel layer; said crystalline oxide semiconductor film contains In and a positive divalent element; said positive divalent element is one or more elements selected from Zn, Mg, Cu, Co, Ni and Ca; and an atomic ratio of the In [In] and the positive divalent element [X] by the formula [X]/([X]+[In]) is such that 0.0001≦
[X]/([X]+[In])≦
0.5. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
- a film-forming step in which an amorphous oxide film is formed as a channel layer;
-
18. An active matrix type image display apparatus provided with a light control element and a field-effect type transistor for driving said light control element,
wherein an active layer of said field-effect type transistor is a crystalline oxide semiconductor and the electron carrier concentration of said active layer is less than 2× - 1017/cm3,
said crystalline semiconductor oxide is a polycrystalline oxide containing In and one or more positive divalent elements selected from Zn, Mg, Cu, Ni, Co and Ca; and an atomic ratio of said In [In] and said positive divalent element [X] by the formula [X]/([X]+[In]) is 0.0001 to 0.13. - View Dependent Claims (19, 20, 21, 22)
- 1017/cm3,
-
23. A semiconductor device comprising a crystalline oxide as an N-type semiconductor, wherein the electron carrier concentration of said crystalline oxide is less than 2×
- 1017/cm3,
wherein said crystalline oxide N-type semiconductor is a polycrystalline oxide containing In and one or more positive divalent element selected from Zn, Mg, Cu, Ni, Co and Ca; and an atomic ratio of said In [In] and said positive divalent element [X] by the formula [X]/([X]+[In]) is 0.0001 to 0.13. - View Dependent Claims (24, 25, 26, 27, 28, 29, 30, 31, 32)
- 1017/cm3,
Specification