An Assessment of the Radiation Tolerance of Collector Diffusion Isolation Bipolar Technology

A systematic assessment has been made of the tolerance to various radiation effects for the CDI bipolar integrated circuit fabrication technology. The study is based on the performance of both individual devices and circuit building blocks covering a range of applications from SSI to VLSI. The technology has not previously been reported in the context of its radiation performance. A number of properties have been recognised which increase the tolerance of the CDI technology to radiation. Of advantage are the fully diffused collector region and the heavily diffused base surface layer. The identified attributes include inherent latchup resistance, a high degree of tolerance to cumulative ionisation dose and to neutron displacement damage, and a reasonable transient upset behaviour.