Abstract

sub-100 nm range. It is expected that the nano-CMOS technology will governed the IC manufacturing for at least another couple of decades. Though there are many challenges ahead, further down-sizing the device to a few nanometers is still on the schedule of International Technology Roadmap for Semiconductors (ITRS). Several technological options for manufacturing nano-CMOS microchips have been available or will soon be available. This paper reviews the challenges of nano-CMOS downsizing and manufacturing. We shall focus on the recent progress on the key technologies for the nano-CMOS IC fabrication in the next fifteen years. 1. Historical Review Among numerous great inventions made in the 20th century, electronics is the most important one. According to a recent survey [1], “Electronic End Equipment ’ has become the base of all human political and economical activities staked a share of the world’s total GDP of about 30,000 billion US dollars. Almost every thing related to human activities, such as power generation, transportation, entertainment, medical care, is now provided and controlled by electronics. Semiconductor, being the key component of the “Electronic End Equipment”, is a strategically important technology for all countries (see Fig.1). The electronic circuit development has been accomplished with the downscaling of component size since the replacement of vacuum tubes with transistors 40 years ago (see Fig.2) [2-3]. The circuit characteristics have benefited a lot from the downsizing. We are now able to integrate millions of CMOS transistors in the nanoscale in a silicon chip with few centimeters square. Right now the operation speed of the latest microprocessor has already reached 3 GHz and is expected to increase further [5] (see Fig.2), although recent trend indicates that the increase of the clock frequency may be gradually saturated. The CMOS integrated circuits as well as their core device technology are expected to evolve further for at least a couple of decades and their importance will be further increased in future intelligent society.