Patent application number | Description | Published |
20100213460 | THIN FILM TRANSISTOR, METHOD FOR MANUFACTURING THE SAME, AND SEMICONDUCTOR DEVICE - In a thin film transistor, an increase in off current or negative shift of the threshold voltage is prevented. In the thin film transistor, a buffer layer is provided between an oxide semiconductor layer and each of a source electrode layer and a drain electrode layer. The buffer layer includes a metal oxide layer which is an insulator or a semiconductor over a middle portion of the oxide semiconductor layer. The metal oxide layer functions as a protective layer for suppressing incorporation of impurities into the oxide semiconductor layer. Therefore, in the thin film transistor, an increase in off current or negative shift of the threshold voltage can be prevented. | 08-26-2010 |
20110063339 | DRIVING METHOD OF DISPLAY DEVICE AND DISPLAY DEVICE - It is an object to reduce power consumption of a display device which can perform multi-gray scale display and to suppress deterioration of an element included in the display device. The usage of a display device includes a first initialization period in which the gray scale level of an entire pixel portion is converted into a first gray scale level and a second initialization period in which the gray scale level of an entire pixel portion is converted into a second gray scale level. In the first initialization period, scanning of a plurality of signals and weighting of a holding period of each signal are performed. Therefore, the small number of scanning of signals can realize voltage application for an appropriate time with respect to each of a plurality of gray scale storage display elements included in the display device. | 03-17-2011 |
20110210327 | LIQUID CRYSTAL DISPLAY DEVICE - An object is to reduce parasitic capacitance of a signal line included in a liquid crystal display device. A transistor including an oxide semiconductor layer is used as a transistor provided in each pixel. Note that the oxide semiconductor layer is an oxide semiconductor layer which is highly purified by thoroughly removing impurities (hydrogen, water, or the like) which become electron suppliers (donors). Thus, the amount of leakage current (off-state current) can be reduced when the transistor is off. Therefore, a voltage applied to a liquid crystal element can be held without providing a capacitor in each pixel. In addition, a capacitor wiring extending to a pixel portion of the liquid crystal display device can be eliminated. Therefore, parasitic capacitance in a region where the signal line and the capacitor wiring intersect with each other can be eliminated. | 09-01-2011 |
20110241011 | FIELD-SEQUENTIAL DISPLAY DEVICE - A first transistor in which an image signal is input to one of a first source and a first drain through an image signal line and a first scan signal is input to the first gate through a first scan signal line; a capacitor whose one of two electrodes is electrically connected to the other of the first source and the first drain of the first transistor; a second transistor in which one of a second source and a second drain is electrically connected to the other of the first source and the first drain of the first transistor and a second scan signal is input to a second gate through a second scan signal line; and a liquid crystal element whose first electrode is electrically connected to the other of the second source and the second drain of the second transistor. | 10-06-2011 |
20120286278 | THIN FILM TRANSISTOR, METHOD FOR MANUFACTURING THE SAME, AND SEMICONDUCTOR DEVICE - In a thin film transistor, an increase in off current or negative shift of the threshold voltage is prevented. In the thin film transistor, a buffer layer is provided between an oxide semiconductor layer and each of a source electrode layer and a drain electrode layer. The buffer layer includes a metal oxide layer which is an insulator or a semiconductor over a middle portion of the oxide semiconductor layer. The metal oxide layer functions as a protective layer for suppressing incorporation of impurities into the oxide semiconductor layer. Therefore, in the thin film transistor, an increase in off current or negative shift of the threshold voltage can be prevented. | 11-15-2012 |
20130122667 | THIN FILM TRANSISTOR, METHOD FOR MANUFACTURING THE SAME, AND SEMICONDUCTOR DEVICE - In a thin film transistor, an increase in off current or negative shift of the threshold voltage is prevented. In the thin film transistor, a buffer layer is provided between an oxide semiconductor layer and each of a source electrode layer and a drain electrode layer. The buffer layer includes a metal oxide layer which is an insulator or a semiconductor over a middle portion of the oxide semiconductor layer. The metal oxide layer functions as a protective layer for suppressing incorporation of impurities into the oxide semiconductor layer. Therefore, in the thin film transistor, an increase in off current or negative shift of the threshold voltage can be prevented. | 05-16-2013 |
20130299825 | DISPLAY DEVICE HAVING AN OXIDE SEMICONDUCTOR TRANSISTOR - An object is to reduce parasitic capacitance of a signal line included in a liquid crystal display device. A transistor including an oxide semiconductor layer is used as a transistor provided in each pixel. Note that the oxide semiconductor layer is an oxide semiconductor layer which is highly purified by thoroughly removing impurities (hydrogen, water, or the like) which become electron suppliers (donors). Thus, the amount of leakage current (off-state current) can be reduced when the transistor is off. Therefore, a voltage applied to a liquid crystal element can be held without providing a capacitor in each pixel. In addition, a capacitor wiring extending to a pixel portion of the liquid crystal display device can be eliminated. Therefore, parasitic capacitance in a region where the signal line and the capacitor wiring intersect with each other can be eliminated. | 11-14-2013 |
20130315021 | SEMICONDUCTOR DEVICE AND METHOD FOR DRIVING SEMICONDUCTOR DEVICE - A semiconductor device capable of simply performing power gating and a driving method thereof are provided. Power gating is started passively (automatically in the case of satisfying predetermined conditions). Specifically, the semiconductor device includes a transistor for selecting whether a power source voltage is supplied or not to a functional circuit. The power gating is started by turning off the transistor in the case where a voltage between a source and a drain is less than or equal to a predetermined voltage. Therefore, complicated operation is not needed at the time of starting power gating. Specifically, it is possible to start power gating without a process for predicting the timing at which an arithmetic operation performed in the functional circuit is terminated. As a result, it is possible to start power gating easily. | 11-28-2013 |
20130326151 | MEMORY MANAGEMENT SYSTEM AND PROGRAM - To reduce power consumption of a computer or the like, a nonvolatile memory divided into a plurality of segments is applied to main memory used for virtual storage management. Thus, power supply even to a segment having a physical address that is being used can be stopped. As a result, power consumption of the computer or the like performing virtual storage management can be reduced. | 12-05-2013 |
20140117352 | THIN FILM TRANSISTOR, METHOD FOR MANUFACTURING THE SAME, AND SEMICONDUCTOR DEVICE - In a thin film transistor, an increase in off current or negative shift of the threshold voltage is prevented. In the thin film transistor, a buffer layer is provided between an oxide semiconductor layer and each of a source electrode layer and a drain electrode layer. The buffer layer includes a metal oxide layer which is an insulator or a semiconductor over a middle portion of the oxide semiconductor layer. The metal oxide layer functions as a protective layer for suppressing incorporation of impurities into the oxide semiconductor layer. Therefore, in the thin film transistor, an increase in off current or negative shift of the threshold voltage can be prevented. | 05-01-2014 |