초록 ▼

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

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.

대표청구항 ▼

A process control system for a semiconductor vapor growing apparatus manufacturing semiconductor devices in batches wherein operating characteristics of said semiconductor vapor growing apparatus vary from batch to batch, comprising: a reaction furnace for vapor phase growing a semiconductor on a se

A process control system for a semiconductor vapor growing apparatus manufacturing semiconductor devices in batches wherein operating characteristics of said semiconductor vapor growing apparatus vary from batch to batch, comprising: a reaction furnace for vapor phase growing a semiconductor on a semiconductor substrate including means for heating said semiconductor substrate; means for supplying various gases to said furnace necessary for vapor phase growth of said semiconductor; a pipe line network interconnecting said reaction furnace and said supplying means; valve means mounted in said pipe line network for controlling supply of commanded quantities of said gases to said reaction furnace; and control means for: (a) storing a process program including thickness data and resistivity data for a vapor phase grown layer formed on said substrate for a predetermined batch and optimum values of flow quantities of said different gases and a sequence time for said thickness data and said resistivity data for said predetermined batch, and storing a correlation between that thicknesses and resistivities and interbatch variations for batches subsequent to said predetermined batch; (b) determining a flow quantity and a sequence time for said predetermined batch from said stored process program; (c) determining correction values for a subsequent batch, subsequent to said predetermined batch, to correct for interbatch variations in operating characteristics of said reaction furnace by determining correction values for said sequence time and said flow quantity for said predetermined batch using said correlation and an indication of a number of batches subsequent to said predetermined batch and target thickness and target resistivity values; (d) storing a step-sequence program for said subsequent batch based on said optimum values; (e) correcting said sequence program in accordance with the determined correction values; and (f) supplying control signals based on said corrected sequence program to said valve means to control an amount of said gas, and to said reaction furnace to control a sequence time.