Modern semiconductor logic families

A review is given of logic families developed and used during the past twelve years, of which RTL and DTL are mainly of historical interest, now being nearly completely superseded by TTL. The bipolar technology used in the production of these logic families is discussed in brief detail, as well as the MOS technology, in its various forms, which has led to newer families, notably C-MOS logic, with electrical characteristics superior to TTL in some aspects. Present trends in both technologies seem to indicate that the promising silicon-on-sapphire C-MOS development program will be overshadowed by the production of a new bipolar logic, multi-collector logic (MCL), which is inherently suitable for high-density LSI digital circuits. In conclusion, some consideration is given to the influence of all the various factors on the local manufacture of custom-made digital ICs.