Introduction to Lithography

Abstract

It is hard to think of an invention that has had a greater influence on the mass production of devices that have enabled humankind to communicate information with printed matter or photons or electrons or ions, or even with atoms, than lithography. The information superhighway and pathways of our present age—the information age—are literally paved with chips of crystalline silicon by lithography. Nearly every book, magazine, newspaper, brochure, flyer, catalog, and other print pieces that have been produced during the last 300 years and before the digital age of the last few decades have been printed with offset lithography. Nearly every integrated circuit (IC) in the chips that run the computers and telecommunication systems that power the information superhighway, as well as medical devices, electronics, home and industrial appliances, automobiles, and airplanes—to mention but a few—are made by semiconductor lithography. Without such ICs, we would have no powerful computers, no large-scale automation, no communication satellites, nor even any space exploration. There would certainly be no electronic calculators or digital watches, no transistor radios, portable tape recorders, personal digital assistants, internet, cell phones, etc. Many diagnostic procedures in medicine and dentistry rely on ICs, as do heart pacemakers and modern hearing aids. The impact of all of these things on our lives is tremendous. For instance, we can watch events on our television sets or mobile phones, or on the Internet, as they are happening thousands of miles away. We can withdraw our money from automatic teller machines almost everywhere in the world, without the aid of a bank clerk, whose function has been transformed from that of an accounts keeper to one of an intermediary between the customer and the computer. Many products are now manufactured, assembled, and shipped today by automatic machines that rely on ICs for their operation. Airplanes are guided by computer-controlled systems, and even airline seats are reserved worldwide by an instantaneous computer booking system. The list is almost endless and is growing every day. A world without lithography would be unrecognizable to anyone of us today, although we may not always be cognizant of its pervasiveness and reach in our daily lives. Lithography underpins most of the technical inventory of modern life.