Study of the Gamma‐ray Effects on Operational Amplifier Characteristics

Abstract

Exposing the "µA 741C" Operational-Amplifiers to gamma-rays with different doses up to 3.5x106 rad was shown to seriously affect their electrical characteristics. Consequently, the devices lose their main features as a result of major defects that cause deviation in the basic behaviors of the system. The differential-mode gain and input resistance values were dropped from 185 V/mV to 70 V/mV and from 9x106 ohm to 1.5x106 ohm respectively. Also, the offset voltage adjustment range was decreased from the band (-12 to +14) mV down to (-1.50 to +2.0) mV. The common-mode rejection ratio which had, as well, an initial value of 100 dB before irradiation reaches a value of 2.0 dB after exposure to 3.5x106 rad. On the other hand, the power supply rejection ratio and input offset voltage and current were shown to have a pronounced increase as a result of gamma exposure. Their values reach 430 µV/V, 75 mV and 50 nA although they have initial values of 20 µV/V, 5.0 mV and 1.0 nA respectively.

Operation of Bidirectional Switches (DIAC) and Silicon Controlled Rectifiers (SCR) in Gamma‐Radiation Environment

“…When high energy radiation is incident on a semiconductor device, energy is deposited in the semiconductor via two mechanisms [6][7][8][9][10][11][12][13][14][15][16][17], atomic collisions and electronic ionization. The relative importance of these two mechanisms in a semiconductor structure depends both on the type of radiation and the nature of the device.…”