Toshiba Kikai Kabushiki Kaisha

Hitoshi Ebata

Takao Manabe

Yoshizo Komiyama

Shoichi Shin

Hideo Kawakami

Shigetugu Matunaga

Shouichi Shin

In a semiconductor vapor phase growing apparatus of the type disclosed in U.S. Pat. No. 4,430,959 dated Feb. 14, 1984, the thickness and resistivity of the semiconductor grown on a substrate by vapor phase growing technique are controlled by a sequence program. The content of the sequence program is corrected to approach a target thickness and a target resistivity at each batch operation. In a modification, an auxiliary mass flow valve is provided for each main mass flow valve and when the main mass flow valve becomes faulty, it is substituted by the auxiliary mass flow valve so as to continue the normal operation of the vapor phase growing apparatus.

Process control system of semiconductor vapor phase growth apparatus

In a semiconductor vapor phase growing apparatus wherein a semiconductor wafer is heated in a reaction furnace, and an output of a source for heating, the temperature of the wafer, and flow quantities of gases supplied to the reaction furnace for vapor phase growing a semiconductor on the wafer by a chemical reaction of the gases are controlled by a control unit according to a predetermined sequences, there are provided a temperature detector for detecting the temperature of the wafer and output control means controlling the output of the source according to a given reference value. The control unit is consitituted by memory means storing a program of executing the sequences and linearly raising and lowering the wafer temperature at a predetermined temperature gradient in a plurality of divided time lateral units by making different the rates of temperature change in respective time interval units, and a CPU for processing the program.

Semiconductor vapor phase growing apparatus

Process control system of semiconductor vapor phase growing apparatus

An apparatus for positioning a plurality of semiconductor substrates on a movable, support in a desired pattern, in a semiconductor vapor phase growing apparatus. A memory is provided for storing two dimensional data corresponding to the desired pattern. The desired pattern is predetermined by the sizes of the substrates and the space available on the flat support. A loading/unloading device loads and unloads the substrates on the support at positions corresponding to the two-dimensional data read from the memory. A positioning device positions the support so that the substrates can be loaded and unloaded at the predetermined positions. A control device synchronizes the movement of the loading/unloading device and the positioning device in accordance with the selected position so that the substrates are loaded and unloaded on the flat support in the desired pattern.

In apparatus for vapor phase growing N or P type semiconductor layers on semiconductor substrates supported by a rotary support disposed in a reaction furnace, and various types of gases are admitted into the furnace through a pipe line network and valves, there is provided a control device for ON-OFF controlling the valves according to a predetermined program. The control device comprises a memory region for storing a process program group including a group of process programs including informations regarding a time for designating a process of vapor phase growth in the reaction furnace, gases utilized, flow quantity thereof and furnace temperature, and a system program that decodes the program group for producing control signals for the valves.

When cutting a groove of a predetermined contour through a plate shaped workpiece with a fret saw blade, various program data regarding the direction of movements of the fret saw blade and the contour of the groove to be cut are stored in a memory device. The fret saw blade is moved in a direction instructed by the memory device and the orientation of the saw blade is controlled at the starting point of each segment of the groove.

Method and apparatus for controlling orientation of tools

In a machine for cutting grooves of a given pattern through a blank with a fret saw blade, openings for receiving the fret saw blade at the cutting starting points of the grooves are determined such that the center of each opening is positioned at a point spaced from a cutting start point by a distance equal to one half of the width of the fret saw blade in a direction opposite to the direction of cutting the groove.

Method of determining position of openings adapted to receive fret saw

In an automatic sawing machine wherein a workpiece is moved in two orthogonal directions by a profile control or a numerical control so as to cut a groove of a predetermined profile, the opposite ends of the fret saw blade are synchronously driven by independent pulse motors so as to direct the fret saw blade always in the tangential direction of the profile.

Growing community of inventors

Mishima, Japan

Hitoshi Ebata