In fabricating a thin film transistor, an active layer comprising a silicon semiconductor is formed on a substrate having an insulating surface Hydrogen is introduced into The active layer A thin film comprising SiO x N y is formed to cover the active layer and then a gate insulating film comprising a silicon oxide film formed on the thin film comprising SiO x N y  Also, a thin film comprising SiO x N y is formed under the active layer The active layer includes a metal element at a concentration of 1×10 15 to 1×10 19 cm −3 and hydrogen at a concentration of 2×10 19 to 5×10 21 cm −3 

Semiconductor device and method for forming the same

LED pixel structures and methods that improve brightness uniformity by reducing current nonuniformities in a light-emitting diode of the pixel structures are disclosed.

Active matrix light emitting diode pixel structure and concomitant method

An active matrix display device having a pixel structure in which pixel electrodes, gate wirings and source wirings are suitably arranged in the pixel portions to realize a high numerical aperture without increasing the number of masks or the number of steps. The device comprises a gate electrode and a source wiring on an insulating surface, a first insulating layer on the gate electrode and on the source wiring, a semiconductor layer on the first insulating film, a second insulating layer on the semiconductor film, a gate wiring connected to the gate electrode on the second insulating layer, a connection electrode for connecting the source wiring and the semiconductor layer together, and a pixel electrode connected to the semiconductor layer.

Semiconductor Device and Method of Fabricating the Same

Mo-gate n-channel poly-Si thin-film transistors (TFT's) have been fabricated for the first time at a low processing temperature of 260°C. A 500-1000-A-thick a-Si:H was successfully crystallized by XeCl excimer laser (308nm) annealing without heating a glass substrate. TFT's were fabricated in the crystallized Si film. The channel mobility of the TFT was 180cm2/V.s when the a-Si:H was crystallized by annealing with a laser having an energy density of 200 mJ/cm2. This result shows that high-speed silicon devices can be fabricated at a low temperature using XeCl excimer laser annealing.

XeCl Excimer laser annealing used in the fabrication of poly-Si TFT's

Pulse circuits for measuring the capacitance to ground of a plate may be used in control equipment to provide an indication of the proximity of a person or object to be sensed. Pulse circuits are disclosed that are made from sets of three or more electrical switching elements arranged so that each of the switching elements has one side electrically connected to either a supply voltage or to an electrical ground. These arrangements are compatible with existing integrated circuit fabrication technology. In addition, the circuitry can be configured as a proximity sensing switch that requires only a two wire connection to a host apparatus.

Charge transfer capacitance measurement circuit

High-performance poly-Si TFTs were fabricated by a low-temperature 600 degrees C process utilizing hard glass substrates. To achieve low threshold voltage (V/sub TH/) and high field-effect mobility ( mu /sub FE/), the conditions for low-pressure chemical vapor deposition of the active layer poly-Si were optimized. Effective hydrogenation was studied using a multigate (maximum ten divisions) and thin-poly-Si-gate TFTs. The crystallinity of poly-Si after thermal annealing at 600 degrees C depended strongly on the poly-Si deposition temperature and was maximum at 550-560 degrees C. The V/sub TH/ and mu /sub FE/ showed a minimum and a maximum, respectively, at that poly-Si deposition temperature. The TFTs with poly-Si deposited at 500 degrees C and a 1000-AA gate had a V/sub TH/ of 6.2 V and mu /sub FE/ of 37 cm/sup 2//V-s. The high-speed operation of an enhancement-enhancement type ring oscillator showed its applicability to logic circuits. The TFTs were successfully applied to 3.3-in.-diagonal LCDs with integration of scan and data drive circuits. >

High performance low-temperature poly-Si n-channel TFTs for LCD

A method for driving a liquid crystal element including a ferroelectric liquid crystal sandwiched between a pair of substrates having electrodes on their opposite surfaces is disclosed. A pulse voltage for defining the light transmitting state of the liquid crystal element is applied to the ferroelectric liquid crystal. Before and/or after the application of the pulse voltage, the ferroelectric liquid crystal is applied with a voltage signal which renders the average value of voltages applied to the ferroelectric liquid crystal equal to zero.

Method for driving liquid crystal element employing ferroelectric liquid crystal

The relationship between transferred charge in the active layer of a thin-film electroluminescent (TFEL) cell and EL device characteristics has been investigated electrically. Making use of a charge density-voltage characteristic measuring system based on a Sawyer-Tower circuit, a general formula for the input power density was found to be given by twice the product of the frequency, the threshold voltage of the active layer, and the transferred-charge density. From this formula, the luminous efficiency could be estimated, once the dependence of the luminance upon the frequency and the transferred charge density was found. At a frequency smaller than the inverse of twice the luminous decay time, e.g. 500 Hz in the ZnS:Mn case, the luminance was found to be proportional to the product of frequency and transferred charge density. Hence, the luminous efficiency becomes constant with a value 2–2.5 times larger than that for 5 or 1 kHz drive conditions.

https://iopscience.iop.org/article/10.1143/JJAP.26.1482/pdf

Transferred Charge in the Active Layer and EL Device Characteristics of TFEL Cells

Complementary thin film transistors (C-TFT) formed on an insulating substrate, comprising a pair of highly resistive n-type silicon islands (2, 20), a pair of heavily doped n-type regions (12, 13) formed on one (2) of the islands to form source and drain regions of n-channel TFT, a pair of contacts (170, 180) formed on the surface of the other island (20) and establishing a high potential barrier when the underlying region is of n-type and a low potential barrier when the underlying region is inverted to be of p-type. The process for manufacturing complementary TFTs can be simplified significantly.

Thin film semiconductor device and method of manufacturing the same

A driving device for a matrix-type display panel using a guest-host type liquid crystal made by adding a pleochroic dye to a nematic-cholesteric phase transition liquid crystal or a chiralnematic phase transition liquid crystal is disclosed in which the display plane of a display panel is divided into a plurality of blocks in such a manner that each block includes a plurality of scanning lines, that is, a plurality of regions are formed, only one of the regions is selected to be used a scanning region, the one-line-at-a-time scanning operation is repeated many times in the scanning region in order to write and display information to perfection, and the regions are selected successively and cyclically to be used as the scanning region.

Hideaki Kawakami

Papers

High performance low-temperature poly-Si n-channel TFTs for LCD

Method for driving liquid crystal element employing ferroelectric liquid crystal

Transferred Charge in the Active Layer and EL Device Characteristics of TFEL Cells

Thin film semiconductor device and method of manufacturing the same

Driving device for matrix-type display panel using guest-host type phase transition liquid crystal