Analytical Investigation of Neutron Hardening of Integrated Injection Logic

An analytical technique is presented for investigating the neutron induced degradation of integrated injection logic (I2L) inverter cells as a function of basic processing variables. The technique combines a one-dimensional semiconductor device code, the PN code, with the circuit analysis code SPICE. Predictions of neutron induced degradation as a function of npn transistor base doping, epitaxial thickness and resistivity and pnp transistor base width are presented for a second generation I2L technology. A comparison of predicted response to experimental data is given for inverter cells fabricated with different npn base doping and epitaxial thickness.