X-Ray Damage Considerations in MOSFET Devices

This paper describes the residual radiation damage in x-ray irradiated MOSFET devices after annealing at 400°C and 760 mm pressure, in pure H2. The total incident energy from a conventional Al target x-ray source was established to simulate lithography exposures using the relatively insensitive x-ray resists presently considered for storage ring x-ray lithography. A radiation threshold damage level to the particular MOSFET devices was estimated by controlling the incident x-ray flux with radiation blocking layers of various thicknesses. From the data, the minimum x-ray resist sensitivity required to expose the MOSFET devices without detrimental effects was estimated. For applications that require resists with lower sensitivity than the estimated minimum value, a multilayer resist structure is proposed to reduce the radiation damage below the threshold value. © 1986, The Electrochemical Society, Inc. All rights reserved.