Chisso Corporation

Renesas Electronics Corporation

Fujitsu Corporation

Ryuji Kobayashi

Kenji Furukawa

Shizuo Murata

Kouichi Kunimune

Masami Tanaka

Minoru Nakayama

Naoyoshi Emoto

Masahide Kobayashi

Takahisa Ito

Yoshimasa Iiduka

The characteristics of a semiconductor laser are improved. In a semiconductor laser having an n type cladding layer, an active layer, and a p type cladding layer, a current block layer is provided. For example, the current block layer is arranged partially between the p type cladding layer and the active layer, and in the overlapping region of the p type cladding layer and the active layer. Thus, in a current narrowing region of the overlapping region of the p type cladding layer and the active layer, the current block layer is arranged, thereby to suppress the current injected into a part of the active layer. This results in the formation of a saturable absorbing region, which causes a difference in intensity of the optical output of the semiconductor laser. This can implement self-pulsation.

Semiconductor device

Provided is a semiconductor laser including: a substrate (semiconductor substrate); an optical waveguide (active layer waveguide) with a mesa structure that includes an active layer (strain-compensated multiple quantum well active layer) including Al, is provided over the semiconductor substrate; a semiconductor protective layer that is provided so as to cover the top and the side of a mesa of the active layer waveguide; a current block layer that is provided so as to embed the active layer waveguide and the semiconductor protective layer; and a clad layer (p-type InP clad layer) that is provided over the semiconductor protective layer and the current block layer, wherein, the semiconductor protective layer has a semiconductor layer (p-type InGaAsP protective layer) that includes As, but does not include Al.

Semiconductor laser and method of manufacturing the same

In the exposure method which carries out optical proximity correction processing for exposure data having a plurality of exposure patterns and exposes a sample in accordance with such corrected exposure data, the exposure patterns to be corrected are converted, in the optical proximity correction processing, into a minus objective pattern and a minus pattern to be deleted from the minus objective pattern, to form corrected exposure data. And, the minus pattern is deleted from the minus objective pattern of the corrected exposure data to bitmap a corrected exposure pattern, to expose a sample in accordance with such bitmapped corrected exposure pattern.

Exposure method utilizing optical proximity corrected exposure patterns, an apparatus for generating optical proximity corrected exposure data, and an exposure apparatus for optical proximity corrected exposure data

An improved liquid crystal-aligning coating composed mainly of a specified high molecule, mainly a polyether polyimide or a polyimide, and capable of controlling the alignment and pretilt angle of liquid crystals; a liquid crystal display element using the coating; and a dinitro compound and a diol compound each as an intermediate of a diamino compound constituting the polyimide ether, are provided, which specified high molecule contains in its molecular long chain, a substituted cyclohexylidene group or a cyclohexylidene group expressed by the formula ##STR1## wherein R.sub.1 to R.sub.6 of the cyclohexyl group each represent H, 1-15C alkyl group, a cyclohexyl group or a cyclohexyl group having 1-15C alkyl group, and may be each the same or partly or totally different.

Liquid crystal-aligning coating and a liquid crystal display element

The present invention provides diamino compounds and liquid crystal aligning films comprising polyimides which are obtained from the said diamino compounds represented by the general formula: ##STR1## wherein R.sub.1 indicates an alkyl group having 3 to 22 carbon atoms, R.sub.2 indicates a hydrogen atom or an alkyl group having 1 to 22 carbon atoms, and R.sub.3 -R.sub.10 indicate a hydrogen atom or a methyl group, respectively. The liquid crystal aligning films are useful for STN mode display cells in realizing a high pretilt angle.

Diamino compounds and liquid crystal aligning films

The present invention is directed to a silicon polyimide precursor composition which has a viscosity suitable for the formation of films by application or another mean and which is capable of forming hard and tough films having excellent heat resistance, low coefficient of thermal expansion and strong adhesive force by heating the films, the above-mentioned films being formed by the chemical bond between silicon and polyimide. Another feature of the present invention is directed to a method for preparing a crosslinked/cured material of the aforesaid silicon polyimide precursor composition. That is, the present invention is connected with a soluble silicon polyimide precursor composition which comprises 0.5 to 40% by weight of a silicon polyimide precursor represented by the following formula (I) on another precursor obtained by imidizing the compound represented by the formula (I) and having a logarithmic viscosity number of 0.05 to 5 dl/g, 0.5 to 40% by weight of a condensate of a silicon compound represented by the following formula (II) and having a logarithmic viscosity number of 0.01 to 0.5 dl/g, and 50 to 99% by weight of a solvent: ##STR1## wherein G is ##STR2## or a hydrogen atom (except the case of n=0), R.sup.1 is independently a tetravalent carbon cyclic aromatic group, R.sup.2 is independently a carbon cyclic aromatic group, R.sup.3 is ##STR3## R.sup.4 is independently methyl or phenyl, R.sup.7 is independently alkyl having 1 to 6 carbon atoms or hydrogen, X is alkoxy, acetoxy or hydroxyl, n is n.gtoreq.0, k is 2.5.ltoreq.k.ltoreq.3, and m is 3.5&lt;m.ltoreq.4.

Silicon polyimide precursor composition

Diamino compounds, dinitro compounds, diol compounds and a process for preparing the diamino compounds which are useful as materials of poly-imide compounds for obtaining aligning films having high pretilt angles in liquid crystal display elements are provided. The diamino compounds are represented by the general formula: ##STR1## wherein R.sub.1 -R.sub.6 are a hydrogen atom or an alkyl group having 1 to 22 carbon atoms, respectively, and R.sub.7 -R.sub.12 are a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, F or Cl respectively.

Growing community of inventors

Kawasaki, Japan

Ryuji Kobayashi