Semiconductor device having a thin film transistor and thin film diode
AssigneeSemiconductor Energy Laboratory Co., Ltd.
InventorsToru Takayama, Yasuhiko Takemura
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Abstract
Amorphous silicon in impurity regions (source and drain regions or N-type or p-type regions) of TFT and TFD are crystallized and activated to lower electric resistance, by depositing film having a catalyst element such as nickel (Ni), iron (Fe), cobalt (Co) or platinum (Pt) on or beneath an amorphous silicon film, or introducing such a catalyst element into the amorphous silicon film by ion implantation and subsequently crystallizing the same by applying heat annealing at an appropriate temperature.
Claims25
A semiconductor circuit having at least one thin film transistor and at least one thin film diode formed on a substrate, wherein
- a semiconductor film that forms an active region (channel-forming region) of said thin film transistor comprises the same layer of a semiconductor film as that of an intrinsic region (I-layer) of said thin film diode, and
- a concentration of a catalyst element for promoting crystallization of semiconductor contained in source and drain regions of said thin film transistor is higher by more than one digit than that in the active region of said thin film transistor.
A semiconductor circuit having at least one thin film transistor and at least one thin film diode formed on a substrate, wherein
- source and drain regions of said thin film transistor, and an n-type region and a p-type region of said thin film diode substantially comprises crystalline semiconductor, and an active region (channel-forming region) of said thin film transistor and an intrinsic region (I-layer) of said thin film diode substantially comprise amorphous semiconductor.
A semiconductor circuit having at least one thin film transistor and at least one thin film diode formed on a substrate, wherein
- a semiconductor film that forms an active region (channel-forming region) of said thin film transistor comprises the same layer of a semiconductor film as that of an n-type region, a p-type region and an intrinsic region (I-layer) of said thin film diode, and
- a concentration of a catalyst element for promoting crystallization of semiconductor contained in a source region and a drain region of the thin film transistor is at 1.times.10.sup.17 cm.sup.-3 or higher and less than 2.times.10.sup.20 cm.sup.-3.
A semiconductor circuit having at least one thin film transistor and at least one thin film diode formed on a substrate, wherein
- a source region and a drain region of said thin film transistor substantially comprise crystalline semiconductor and an n-type region and a p-type region of said thin film diode substantially comprise amorphous semiconductor.
A semiconductor circuit having at least one thin film transistor and at least one thin film diode formed on a substrate, wherein
- a semiconductor film that forms an active region (channel-forming region) of said thin film transistor comprises the same layer of a semiconductor film as that for an n-type region, a p-type region and an intrinsic region (I-layer) of said thin film diode, and
- a concentration of a catalyst element for promoting crystallization of semiconductor contained in the active region of the thin film transistor is at 1.times.10.sup.17 cm.sup.-3 or higher and less than 2.times.10.sup.20 cm.sup.-3.
A semiconductor circuit having at least one thin film transistor and at least one thin film diode formed on a substrate, wherein
- an active region of said thin film transistor substantially comprises crystalline semiconductor and
- an intrinsic region of said thin film diode substantially comprises amorphous semiconductor.
A semiconductor circuit having at least one thin film transistor and at least one thin film diode formed on a substrate, wherein
- a semiconductor film that forms an active region (channel-forming region) of said thin film transistor is the same layer of a semiconductor film as that of an intrinsic region (I-layer) of said thin film diode, and
- a concentration of a catalyst element for promoting crystallization of semiconductor contained in the active region of the thin film transistor and the intrinsic region of said thin film diode is at 1.times.10.sup.17 cm.sup.-3 or higher and less than 2.times.10.sup.20 cm.sup.-3.
A semiconductor circuit having at least one thin film transistor and at least one thin film diode formed on a substrate, wherein
- a width (channel length) of an active region (channel-forming region) of said thin film transistor is shorter than a width of an intrinsic region of said thin film diode,
- the active region of said thin film transistor substantially comprises crystalline semiconductor and
- at least a portion of the intrinsic region of said thin film diode comprises amorphous semiconductor.
A semiconductor device having at least one thin film diode formed on a substrate, wherein
- said thin film diode includes an amorphous semiconductor film at least a portion of which is crystallized by a catalyst element.
Dependencies are inferred from the claim text.