Computer controlled data measurement and analysis system used for measuring switching parameters of semiconductors. [Employs HP 2114B minicomputer; reports contain all applicable coding in assembly language

Abstract

A computer-controlled data acquisition system which was employed to measure the threshold switching parameters of amorphous semiconductors is described. This system is capable of measuring the delay time required for a sample to switch, the electrical energy put into a sample and the charge passing through it during the delay time, and its ambient temperature. With this equipment an experimenter is able to control the magnitude and maximum duration of the voltage applied to a sample, the time interval between applications of voltage, and the load resistor in series with a sample. An HP 2114B minicomputer provides control and analysis capabilities for this system. Basically, this apparatus is a constant voltage pulse generator and signal processor. Major modules of this system are a transistorized high voltage switch, a digitally controlled high voltage resistor and power supply, a low-thermal-noise input-scanner, a precision timer, and two analog integrators. The amplitude of a voltage pulse can be varied from 0V to 1 kV and the maximum duration can be varied from 10 ..mu..s to 300 s. During the voltage pulse, a signal which represents the current through a sample is processed by analog integrators and signal multipliers. If the sample switches to a low-resistance state during a voltage pulse, this equipment automatically detects the event and removes the voltage from the sample to prevent sample deterioration. Following the voltage pulse, a teletypewriter prints the raw data from the integrators, power supply, and timer and the calculated values of the charge and energy input. 44 figures, 2 tables. (auth)