Nec Corporation

Susumu Asada

Shinji Matsui

Koichi Sawahata

Kaori Kurihara

Katsumi Mori

An ion implantation process simulation device includes a Dual Pearson data extracting unit for generating a Dual Pearson data table from ion implantation profile data, a Dual Pearson data for interpolation obtaining unit for obtaining a parameter for use in the interpolation and extrapolation of a dose coefficient from the Dual Pearson data table, a dose coefficient interpolating/extrapolating unit for expressing an ion implantation profile by linear connection of two functions respectively representing an amorphous component and a channeling component, as well as using a dose-independent moment parameter and a coefficient of linear connection dependent on dose to interpolate and extrapolate a logarithmic value of a channeling component dose coefficient with respect to logarithmic values of all dose values, and a simulation result outputting unit for outputting a simulation result.

Ion implantation process simulation device realizing accurate

A three dimensional wiring inductance calculating system taking the wiring as analyzing space expressed as three-dimensional configuration and make discrete the analyzing space into a finite number of partial elements. By solving a Poisson's equation with respect to an electrical potential in the discrete analyzing space, a current value and a current density vector distribution within the wiring are derived. Also, by solving an integral equation of a vector potential including the current density vector at each of points of partial elements within the wiring by making discrete, the vector potential as a boundary condition at a boundary of the wiring is derived. Then, the vector potential is derived by solving a vector potential equation in the discretized analyzing space with taking the vector potential value at the boundary as the boundary condition. A product of the obtained vector potential and the current density vector per unit current value is normalized for deriving an integral sum of the produce within the analyzing space and calculating an inductance of the wiring.

Three dimensional wiring inductance calculation system

Impurity concentration profile is determined for a diffused layer of a semiconductor substrate by repeating a combination of etching of the diffused layer and measuring sheet resistance and/or hall resistance by using electrodes formed on the diffused layer. The etching of the diffused layer by a small amount is repeated in first portions aligned in the depth direction of the diffused layer, followed by etching of adjacent second portions aligned in the depth direction. The etching may be replaced by implanting inactive ions into portions of the diffused layer to generate high resistance for the portions.

Method for determining an impurity concentration profile

A semiconductor multilayer reflector (Distributed Bragg Reflector) includes a plurality of first quarter-wavelength layers each having a high refractive index, a plurality of second quarter-wavelength layers each having a low refractive index, and high concentration impurity doping regions. The first and second layers are piled up alternately, and each of the doping regions is formed at a heterointerface between the first and second layer. In this structure, the width and the height of the potential barrier at the heterointerface becomes small, so that tunnel current flowing through the multilayer reflector is increased.

Semiconductor multilayer reflector and light emitting device with the

A surface emitting laser device has a luminescent layer, a lower distributed Bragg reflector formed below the luminescent layer and an upper distributed Bragg reflector formed over the luminescent layer, and each of the lower and upper distributed Bragg reflectors comprises a high refractive film of gallium arsenide with the minimum forbidden band width at gamma point, an intermediate film of aluminum gallium arsenide and a low refractive film of aluminum gallium arsenide with the minimum forbidden band width outside the gamma point, wherein the aluminum gallium arsenide for the intermediate film has a predetermined forbidden band width, and the forbidden band gap between the high refractive film and the intermediate film is approximately equal to the forbidden band gap between the intermediate film and the low refractive film so that the series resistance of the surface emitting laser device is drastically reduced.

Semiconductor light emitting device with luminescent layer sandwiched

A film of an element is deposited on a semiconductor substrate by passing on the substrate gas containing the element and then irradiating a predetermined portion of the substrate with an electron beam. Then, the gas is decomposed to deposit the element on the substrate so as to form a pattern. By heating the pattern, the element is diffused into the surface of the substrate thus forming a diffused region. The gas is generated by sublimating solid Cr(C.sub.6 H.sub.6).sub.2, Mo(C.sub.6 H.sub.6).sub.2, Mo(C.sub.6 H.sub.6).sub.2, Al(CH.sub.3).sub.3, WCl.sub.6 etc.

Growing community of inventors

Tokyo, Japan

Susumu Asada