Matsushita Electric Industrial Co., Ltd.

Shin-itsu Takehashi

Tetsuo Kawakita

Shigeo Ikuta

Yutaka Nanno

Keizaburo Kuramasu

Kouji Senda

Mayumi Inoue

Hiroaki Fujimoto

Hiroshi Tsutsu

Yoshinao Taketomi

Shinji Umeda

A number of minuscule LDD thin film transistors with high precision are arranged on a substrate for use in a liquid crystal display apparatus or other similar devices. The gate electrode is used as a mask at the time of injecting impurities into the semiconductor layer. To realize an LDD structure, the impurities are injected in two installments. The size of the gate electrode is changed in accordance with the length of the LDD regions between the first and second injections. The size of the gate electrode is changed by means of metal oxidation or dry etching. For precision dry etching of the gate electrode, various ideas are put into forming the photo resist.

Method for fabricating thin film transistor

An active matrix liquid crystal display device has a plurality of unit pixels being arranged in a matrix configuration, each unit pixel being divided into a plurality of subpixels. Each of the subpixels has a subpixel electrode, a pixel transistor connected to the subpixel electrode, and a voltage controlling capacitor connected to the subpixel electrode. A voltage controlling capacitor line for supplying a compensation voltage signal is connected to the voltage controlling capacitor so that after the writing to the subpixel has been completed, the potential of the compensation voltage signal is varied to modulate the potential of the subpixel electrode to be a predetermined voltage, using the voltage controlling capacitor. Such combining of spatial dithering attained by a pixel-dividing technique and a capacitively-coupled driving method eliminates the need for digital-to-analog converter circuits, attains gray scale display based on a digital image signal, and achieves a reduction in power consumption.

Liquid crystal display device, electroluminescent display device, method of driving the devices, and method of evaluating subpixel arrangement patterns

The present invention provides a liquid crystal display device having a liquid crystal display portion, a gate driver circuit, a source driver circuit, and a power supply circuit, where the liquid crystal display portion includes unit pixels with pixel switching elements and pixel electrodes arranged in a matrix. The pixel switching elements are thin film transistors that are made of polycrystalline silicon semiconductor formed on an insulating substrate. The power supply circuit is a charge pump-type power supply circuit, is made of a polycrystalline silicon semiconductor, and is a built-in circuit integrally formed on an insulating substrate. With such a configuration, a liquid crystal display device that greatly reduces power consumption is realized.

Display device

The present invention provide an LDD type TFT having excellent properties, particularly for a liquid crystal display unit. For this purpose, a top gate type LDDTFT gate electrode is converted into a two-stage structure by use of a chemical reaction or plating, and furthermore, into a shape in which an upper portion or a lower portion slightly protrudes on the source electrode side, or the drain electrode side relative to the other portions. Impurities are injected by using this electrode having this structure and shape as a mask. Prior to injection of impurities, the gate insulating film is removed, and a Ti film is formed for preventing hydrogen for dilution from coming in. This is also the case with the LDD-TFT on the bottom gate side.

Thin-film transistor, panel, and methods for producing them

The present invention discloses a semiconductor chip removal method of removing a semiconductor chip having thereon a chip electrode from a board having thereon a board electrode wherein the semiconductor chip is bonded to the board with a resin and these chip and board electrodes are connected together electrically by a wire. This semiconductor chip removal method comprises the following steps of: (a) cutting the bonding wire into two pieces by a cutter that presses its cutting edge against the base of the bonding wire on the board electrode's side; (b) separating the semiconductor chip from the board by a chip remover that forces the semiconductor chip sideways, with the adhesive strength of the resin weakened by the application of heat thereto; and (c) removing the semiconductor chip together with a piece of the bonding wire left on the chip electrode's side.

Growing community of inventors

Daito, Japan

Shin-itsu Takehashi