SHF: Medium: Back to the Future with Printed, Flexible Electronics – Design in a Post-CMOS Era when Transistor Counts Matter Again

Figure 1: Examples of printed, flexible electronics: RFID tags, biomedical monitoring, display and visual e↵ects, smart wings. Images from [1,2, 33, 75] In the early days of the semiconductor industry, designing complex circuits was an art. Skilled practitioners strove for elegant and e cient designs with the highest performance using the fewest possible transistors. By the early 1970’s, with the advent of CMOS integrated circuits, the era of massive scaling had begun. Carver Mead, a semiconductor technology guru at Caltech, exhorted designers to “waste transistors.” He coined the term Moore’s Law based on Gordon Moore’s empirical observation that the number of transistors on integrated circuits seemed to be doubling every two years or so. As feature sizes have dropped from millimeters, to micrometers, to nanometers, the transistor counts of integrated circuits have increased from thousands, to millions, to billions. Throughout the history of very large scale integration (VLSI), achievable clock speed and power consumption have been the dominant metrics of the technology. With billions of transistors per integrated circuit, Carver Mead’s advice to waste transistors – or at least ignore transistor counts as a metric – seems as prescient as ever.