摘要:
An object is to control composition and a defect of an oxide semiconductor. Another object is to increase field effect mobility of a thin film transistor and to obtain a sufficient on-off ratio with off current suppressed. The oxide semiconductor is represented by InMO3(ZnO)n (M is one or a plurality of elements selected from Ga, Fe, Ni, Mn, Co, and Al, and n is a non-integer number of greater than or equal to 1 and less than 50) and further contains hydrogen. In this case, the concentration of Zn is made to be lower than the concentrations of In and M (M is one or a plurality of elements selected from Ga, Fe, Ni, Mn, Co, and Al). In addition, the oxide semiconductor has an amorphous structure. Here, n is preferably a non-integer number of greater than or equal to 50, more preferably less than 10.
摘要:
A highly reliable semiconductor device which includes a thin film transistor having stable electric characteristics, and a manufacturing method thereof. In the manufacturing method of the semiconductor device which includes a thin film transistor where a semiconductor layer including a channel formation region is an oxide semiconductor layer, heat treatment which reduces impurities such as moisture to improve the purity of the oxide semiconductor layer and oxidize the oxide semiconductor layer (heat treatment for dehydration or dehydrogenation) is performed. Not only impurities such as moisture in the oxide semiconductor layer but also those existing in a gate insulating layer are reduced, and impurities such as moisture existing in interfaces between the oxide semiconductor layer and films provided over and under and in contact with the oxide semiconductor layer are reduced.
摘要:
An object is to manufacture and provide a highly reliable semiconductor device including a thin film transistor with stable electric characteristics. In a method for manufacturing a semiconductor device including a thin film transistor in which a semiconductor layer including a channel formation region serves as an oxide semiconductor film, heat treatment for reducing impurities such as moisture (heat treatment for dehydration or dehydrogenation) is performed after an oxide insulating film serving as a protective film is formed in contact with an oxide semiconductor layer. Then, the impurities such as moisture, which exist not only in a source electrode layer, in a drain electrode layer, in a gate insulating layer, and in the oxide semiconductor layer but also at interfaces between the oxide semiconductor film and upper and lower films which are in contact with the oxide semiconductor layer, are reduced.
摘要:
An object is to manufacture and provide a highly reliable semiconductor device including a thin film transistor with stable electric characteristics. In a method for manufacturing a semiconductor device including a thin film transistor in which a semiconductor layer including a channel formation region serves as an oxide semiconductor film, heat treatment for reducing impurities such as moisture (heat treatment for dehydration or dehydrogenation) is performed after an oxide insulating film serving as a protective film is formed in contact with an oxide semiconductor layer. Then, the impurities such as moisture, which exist not only in a source electrode layer, in a drain electrode layer, in a gate insulating layer, and in the oxide semiconductor layer but also at interfaces between the oxide semiconductor film and upper and lower films which are in contact with the oxide semiconductor layer, are reduced.
摘要:
An object is to control composition and a defect of an oxide semiconductor, another object is to increase a field effect mobility of a thin film transistor and to obtain a sufficient on-off ratio with a reduced off current. A solution is to employ an oxide semiconductor whose composition is represented by InMO3(ZnO)m, where M is one or a plurality of elements selected from Ga, Fe, Ni, Mn, Co, and Al, and m is preferably a non-integer number of greater than 0 and less than 1. The concentration of Zn is lower than the concentrations of In and M. The oxide semiconductor has an amorphous structure. Oxide and nitride layers can be provided to prevent pollution and degradation of the oxide semiconductor.
摘要:
An object is to provide a display device which operates stably with use of a transistor having stable electric characteristics. In manufacture of a display device using transistors in which an oxide semiconductor layer is used for a channel formation region, a gate electrode is further provided over at least a transistor which is applied to a driver circuit. In manufacture of a transistor in which an oxide semiconductor layer is used for a channel formation region, the oxide semiconductor layer is subjected to heat treatment so as to be dehydrated or dehydrogenated; thus, impurities such as moisture existing in an interface between the oxide semiconductor layer and the gate insulating layer provided below and in contact with the oxide semiconductor layer and an interface between the oxide semiconductor layer and a protective insulating layer provided on and in contact with the oxide semiconductor layer can be reduced.
摘要:
The semiconductor device includes a driver circuit including a first thin film transistor and a pixel including a second thin film transistor over one substrate. The first thin film transistor includes a first gate electrode layer, a gate insulating layer, a first oxide semiconductor layer, a first oxide conductive layer, a second oxide conductive layer, an oxide insulating layer which is in contact with part of the first oxide semiconductor layer and which is in contact with peripheries and side surfaces of the first and second oxide conductive layers, a first source electrode layer, and a first drain electrode layer. The second thin film transistor includes a second gate electrode layer, a second oxide semiconductor layer, and a second source electrode layer and a second drain electrode layer each formed using a light-transmitting material.
摘要:
It is an object to provide a light-emitting device in which plural kinds of circuits are formed over one substrate and plural kinds of thin film transistors corresponding to characteristics of the plural kinds of circuits are provided. An inverted coplanar thin film transistor in which an oxide semiconductor layer overlaps with a source electrode layer and a drain electrode layer is used for a pixel, and a channel-etched thin film transistor is used for a driver circuit. A color filter layer is provided between the pixel thin film transistor and a light-emitting element which is electrically connected to the pixel thin film transistor so as to overlap with the light-emitting element.
摘要:
An object is to provide a display device with excellent display characteristics, where a pixel circuit and a driver circuit provided over one substrate are formed using transistors which have different structures corresponding to characteristics of the respective circuits. The driver circuit portion includes a driver circuit transistor in which a gate electrode layer, a source electrode layer, and a drain electrode layer are formed using a metal film, and a channel layer is formed using an oxide semiconductor. The pixel portion includes a pixel transistor in which a gate electrode layer, a source electrode layer, and a drain electrode layer are formed using an oxide conductor, and a semiconductor layer is formed using an oxide semiconductor. The pixel transistor is formed using a light-transmitting material, and thus, a display device with higher aperture ratio can be manufactured.
摘要:
The semiconductor device includes a driver circuit portion including a driver circuit and a pixel portion including a pixel. The pixel includes a gate electrode layer having a light-transmitting property, a gate insulating layer, a source electrode layer and a drain electrode layer each having a light-transmitting property provided over the gate insulating layer, an oxide semiconductor layer covering top surfaces and side surfaces of the source electrode layer and the drain electrode layer and provided over the gate electrode layer with the gate insulating layer therebetween, a conductive layer provided over part of the oxide semiconductor layer and having a lower resistance than the source electrode layer and the drain electrode layer, and an oxide insulating layer in contact with part of the oxide semiconductor layer.