Semiconductor Energy Laboratory Co., Ltd.

Ichiro Uehara

Hideomi Suzawa

Shunpei Yamazaki

Hideto Ohnuma

Masaharu Nagai

Kazuhiro Toshima

Akira Sugawara

Nobuhiro Tanaka

In an EL element having an anode, an insulating film (bump) formed on the anode, and an EL film and a cathode formed on the insulating film, each of a bottom end portion and a top end portion of the insulating film is formed so as to have a curved surface. The taper angle of a central portion of the insulating film is set within the range from 35&#xb0; to 70&#xb0;, thereby preventing the gradient of the film forming surface on which the EL film and the cathode are to be formed from being abruptly changed. On the thus-formed film forming surface, the EL film and the cathode can be formed so as to be uniform in thickness, so that occurrence of discontinuity in each of EL film and the cathode is prevented.

Display device and method of fabricating the display device

Light emitting device

In the manufacturing method of a GOLD structured TFT having a gate electrode of double-layered structure, in which, compared to a second layer gate electrode, the first layer gate electrode is thinner in film thickness and longer in dimension of the channel direction, by controlling the density of the photo-absorbent contained in a positive type resist such as diazonaphthoquinone (DNQ)-novolac resin series, the taper angle of the side wall is controlled to a desired angle range so that the angle thereof becomes smaller. Owing to this, it is possible to control the retreat amount of the resist when carrying out dry etching and the dimension of L, area to a desired dimensional range so that the dimension thereof becomes larger.

Manufacturing method of semiconductor device

Formation of LDD structures and GOLD structures in a semiconductor device is conventionally performed in a self aligning manner with gate electrodes as masks, but there are many cases in which the gate electrodes have two layer structures, and film formation processes and etching processes become complex. Further, in order to perform formation of LDD structures and GOLD structures only by processes such as dry etching, the transistor structures all have the same structure, and it is difficult to form LDD structures, GOLD structures, and single drain structures separately for different circuits. By applying a photolithography process for forming gate electrodes to photomasks or reticles, in which supplemental patterns having a function of reducing, the intensity of light and composed of diffraction grating patterns or translucent films, are established, GOLD structure, LDD structure, and single drain structure transistors can be easily manufactured for different circuits through dry etching and ion injection process steps.

Method of manufacturing a semiconductor device

In a patterning process of a semiconductor device having inverted stagger type TFTs, a normal photolithography step using diazo naphthoquinone (DNQ)-Novolac resin based positive photo resist is applied, and a problem of the area dependency of the photo resist pattern side wall taper angle may occur. The problem is critical for the reason of influence on variation of an etching shape in a dry-etching step. The present invention has an object to solve the above problem. In a photolithography step, which is patterning step of a semiconductor device having inverted stagger type TFTs, by adjusting a pre-bake temperature or a PEB (post-exposure-bake) temperature, and positively performing evacuation of solvent in a state of a photo resist film, the volume contraction by evacuation of solvent at the post-bake is reduced, and the problem of the area dependency of the photo resist pattern side wall taper angle is solved, which is deformation due to the volume contraction.

Formation of LDD structures and GOLD structures in a semiconductor device is conventionally performed in a self aligning manner with gate electrodes as masks, but there are many cases in which the gate electrodes have two layer structures, and film formation processes and etching processes become complex. Further, in order to perform formation of LDD structures and GOLD structures only by processes such as dry etching, the transistor structures all have the same structure, and it is difficult to form LDD structures, GOLD structures, and single drain structures separately for different circuits. By applying a photolithography process for forming gate electrodes to photomasks or reticles, in which supplemental patterns having a function of reducing the intensity of light and composed of diffraction grating patterns or translucent films, are established, GOLD structure, LDD structure, and single drain structure transistors can be easily manufactured for different circuits through dry etching and ion injection process steps.

In a resist pattern forming method in which bake processing is performed at a temperature not lower than a glass transition temperature in order to obtain the desired sidewall angle, resist removable is difficult. Accordingly, in the resist pattern forming method of performing bake processing at a temperature not lower than a glass transition temperature, a process margin for resist removability cannot be ensured, so that there is the problem that it is impossible to compatibly realize both the formation of a resist pattern having the desired sidewall angle and the resist removability of the resist pattern. The invention aims to solve the problem. A resist pattern including a diazonaphthoquinone (DNQ)-novolac resin type of positive resist is formed, and the resist pattern is irradiated with light within the range of photosensitive wavelengths of a DNQ photosensitizer to perform bake processing on the resist pattern at a temperature not lower than the glass transition temperature of the resist pattern.

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Kanagawa, Japan

Ichiro Uehara