In order to make ion implanter to satisfy the requirements of the semiconductor production processes,the control system of
an implanter must be designed so that its control functions are strong.The instructions from the control computer can be executed rapidly and accurately.When the implanter goes wrong,the control computer can find it promptly and take action to do
abnormity interrupt service effectively.LC19 ion implanter makes use of a single centralized-control computer to control the subsystems.By this method,a complicated control system has been designed to obtain the effective,stable and reliable control of the implanter.The master controller has been designed to receive instructions from the centralized-control computer by way of double port SRAM connected to ISA bus.The computer can send out instructions to A location and B location of the double port SRAM alternately.Then,the master controller tells subcontrollers what they should do by serial port at high speed.The principle is simple,but instructions can be transmitted and executed promptly.Between the master controller and subcontrollers,the communication can be checked making use of a clever method.As soon as the communication breaks off,sub-controllers will reset themselves promptly preventing the implanter from running away.This paper describes the control method and its characteristics at first,then explains the principle and
program flow chart of the master controller.