IP Library Granted Patent US 8,633,487
Granted Patent B2
US 8,633,487 · App. 13/232,119 · Granted Jan 21, 2014

Transistor structure, manufacturing method of transistor structure, and light emitting apparatus

Inventor: Kazuto Yamamoto (Tokyo, JP)
Assignee: Casio Computer Co., Ltd.
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Quick Facts
Patent No.
US 8,633,487
App. No.
13/232,119
Granted
Jan 21, 2014
Kind
B2
Abstract

Disclosed is a transistor structure including: a first thin film transistor including, a first gate electrode; a first insulating film; a first semiconductor film; and a first light blocking film, and a second thin film transistor including, a second semiconductor film; the second insulating film; a second gate electrode; and a second light blocking film, wherein the first semiconductor film and the second semiconductor film include a first region and a second region along a thickness direction from the first insulating film side; and degree of crystallization of silicon of one of the first region or the second region is higher than the degree of crystallization of silicon of the other of the first region or the second region.

Claims (94)

1. A transistor structure comprising:

a first thin film transistor including:

a first gate electrode;

a first insulating film which covers the first gate electrode;

a first semiconductor film which is provided in a position on the first insulating film corresponding to the first gate electrode;

a second insulating film which covers the first semiconductor film; and

a first light blocking film which is provided in a position on the second insulating film corresponding to the first semiconductor film, and

a second thin film transistor including:

a second semiconductor film which is provided on the first insulating film; the second insulating film which covers the second semiconductor film;

a second gate electrode which is provided in a position on the second insulating film corresponding to the second semiconductor film; and

a second light blocking film which is provided in a position below the first insulating film corresponding to the second semiconductor film,

wherein:

the first semiconductor film and the second semiconductor film include a first region and a second region along a thickness direction from a side of the first insulating film, and a degree of crystallization of silicon of one of the first region and the second region is higher than a degree of crystallization of silicon of the other of the first region and the second region;

in the first thin film transistor, the first region in the first semiconductor film constitutes an electric current path of the first semiconductor film; and

in the second thin film transistor, the second region in the second semiconductor film constitutes an electric current path of the second semiconductor film.

2. The transistor structure according to claim 1 , wherein in the first semiconductor film and the second semiconductor film, the other of the first region and the second region has a higher rate of an amorphous silicon region compared to said one of the first region and the second region.

3. The transistor structure according to claim 1 , wherein:

a recessed section is provided in at least a portion of a region on an upper surface of the first semiconductor film corresponding to the first gate electrode;

a recessed section is provided in at least a portion of a region on an upper surface of the second semiconductor film corresponding to the second gate electrode;

the first thin film transistor includes a first source electrode and a first drain electrode provided in at least a portion of a region except the recessed section of the first semiconductor film through an impurity semiconductor film; and

the second thin film transistor includes a second source electrode and a second drain electrode provided in at least a portion of a region except the recessed section of the second semiconductor film through an impurity semiconductor film.

4. The transistor structure according to claim 3 , wherein the recessed section is provided in the second region of the first semiconductor film and the second semiconductor film.

5. The transistor structure according to claim 1 , wherein the first light blocking film and the second light blocking film are formed from a conductive material and are electrically connected to a ground line set to ground potential.

6. A light emitting apparatus comprising:

a light emitting element; and

a transistor structure including:

a first thin film transistor including:

a first gate electrode;

a first insulating film which covers the first gate electrode;

a first semiconductor film which is provided in a position on the first insulating film corresponding to the first gate electrode;

a second insulating film which covers the first semiconductor film; and

a first light blocking film which is provided in a position on the second insulating film corresponding to the first semiconductor film, and

a second thin film transistor including:

a second semiconductor film which is provided on the first insulating film;

the second insulating film which covers the second semiconductor film;

a second gate electrode which is provided in a position on the second insulating film corresponding to the second semiconductor film; and

a second light blocking film which is provided in a position below the first insulating film corresponding to the second semiconductor film,

wherein:

emission of light of the light emitting element is controlled by the first thin film transistor and the second thin film transistor;

the first semiconductor film and the second semiconductor film include a first region and a second region along a thickness direction from a side of the first insulating film, and a degree of crystallization of silicon of one of the first region and the second region is higher than a degree of crystallization of silicon of the other of the first region and the second region;

in the first thin film transistor, the first region in the first semiconductor film constitutes an electric current path of the first semiconductor film; and

in the second thin film transistor, the second region in the second semiconductor film constitutes an electric current path of the second semiconductor film.

7. The light emitting apparatus according to claim 6 , wherein in the first semiconductor film and the second semiconductor film, the other of the first region and the second region has a higher rate of an amorphous silicon region compared to said one of the first region and the second region.

8. The light emitting apparatus according to claim 6 , wherein:

the degree of crystallization of silicon in the first region is higher than the degree of crystallization of silicon in the second region;

the second thin film transistor functions as a switch transistor which controls transmission of a signal to the first thin film transistor; and

the first thin film transistor functions as a driving transistor which flows an electric current to the light emitting element, the electric current being based on a signal transmitted through the second thin film transistor.

9. The light emitting apparatus according to claim 6 , wherein:

the degree of crystallization of silicon in the second region is higher than the degree of crystallization of silicon in the first region;

the first thin film transistor functions as a switch transistor which controls transmission of a signal to the second thin film transistor; and

the second thin film transistor functions as a driving transistor which flows an electric current to the light emitting element, the electric current being based on a signal transmitted through the first thin film transistor.

10. The light emitting apparatus according to claim 6 , further comprising:

a voltage supplying line connected to at least one of the first thin film transistor and the second thin film transistor; and

a conducting layer provided on the voltage supplying line electrically connected to the voltage supplying line and formed from same material as the second gate electrode.

11. The light emitting apparatus according to claim 6 , wherein:

a recessed section is provided in at least a portion of a region on an upper surface of the first semiconductor film corresponding to the first gate electrode;

a recessed section is provided in at least a portion of a region on an upper surface of the second semiconductor film corresponding to the second gate electrode;

the first thin film transistor includes a first source electrode and a first drain electrode provided in at least a portion of a region except the recessed section of the first semiconductor film through an impurity semiconductor film; and

the second thin film transistor includes a second source electrode and a second drain electrode provided in at least a portion of a region except the recessed section of the second semiconductor film through an impurity semiconductor film.

12. The light emitting apparatus according to claim 11 , wherein the recessed section is provided in the second region of the first semiconductor film and the second semiconductor film.

13. The light emitting apparatus according to claim 6 , wherein the first light blocking film and the second light blocking film are formed from a conductive material and are electrically connected to a ground line set to ground potential.

14. A transistor structure comprising:

a first thin film transistor including:

a first gate electrode;

a first insulating film which covers the first gate electrode;

a first semiconductor film which is provided in a position on the first insulating film corresponding to the first gate electrode;

a second insulating film which covers the first semiconductor film; and

a first light blocking film which is provided in a position on the second insulating film corresponding to the first semiconductor film, and

a second thin film transistor including:

a second semiconductor film which is provided on the first insulating film;

the second insulating film which covers the second semiconductor film;

a second gate electrode which is provided in a position on the second insulating film corresponding to the second semiconductor film; and

a second light blocking film which is provided in a position below the first insulating film corresponding to the second semiconductor film,

wherein:

the first semiconductor film and the second semiconductor film include a first region and a second region along a thickness direction from a side of the first insulating film, and a degree of crystallization of silicon of one of the first region and the second region is higher than a degree of crystallization of silicon of the other of the first region and the second region, and

the first light blocking film and the second light blocking film are formed from a conductive material and are electrically connected to a ground line set to ground potential.

15. A light emitting apparatus comprising:

a light emitting element; and

a transistor structure including:

a first thin film transistor including:

a first gate electrode;

a first insulating film which covers the first gate electrode;

a first semiconductor film which is provided in a position on the first insulating film corresponding to the first gate electrode;

a second insulating film which covers the first semiconductor film; and

a first light blocking film which is provided in a position on the second insulating film corresponding to the first semiconductor film, and

a second thin film transistor including:

a second semiconductor film which is provided on the first insulating film;

the second insulating film which covers the second semiconductor film;

a second gate electrode which is provided in a position on the second insulating film corresponding to the second semiconductor film; and

a second light blocking film which is provided in a position below the first insulating film corresponding to the second semiconductor film,

wherein:

emission of light of the light emitting element is controlled by the first thin film transistor and the second thin film transistor;

the first semiconductor film and the second semiconductor film include a first region and a second region along a thickness direction from a side of the first insulating film, and a degree of crystallization of silicon of one of the first region and the second region is higher than a degree of crystallization of silicon of the other of the first region and the second region; and

the first light blocking film and the second light blocking film are formed from a conductive material and are electrically connected to a ground line set to ground potential.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 6, 2016
From: CASIO COMPUTER CO., LTD.
To: SOLAS OLED LTD.
Reel/Frame 040823/0287 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 14, 2011
From: YAMAMOTO, KAZUTO
To: CASIO COMPUTER CO., LTD.
Reel/Frame 026902/0285 →
Priority Claims (2)
JP 2010-205016 · Sep 14, 2010 · national
JP 2010-205024 · Sep 14, 2010 · national
Continuity (1)
Related Publication 20120061675A1 · Mar 15, 2012