We review the birth and development of microelectronics. There are many historical milestone inventions such as transistors, integrated circuits, the planar process, metal-oxide-semiconductor transistors, microprocessors, lithography and copper interconnect technology in which physics theories and achievements played a key role. The future development of microelectronics is also overviewed. Under the drive of social demand and advances in physics and technology microelectronics has been and will continue developing according to Moore's Law with shrinking size but increasing integration. On the other hand, the developments in microelectronics not only provide a strong technology base but also open up new research areas for physics research. As device feature size approaches its physical limit, microelectronics will face new challenges involving material, technology and basic physics, and will develop in a multi-dimensional fashion. As these challenges involve the common theoretical basis of microelectronics and physics, close interaction of the two fields is acquired for future new breakthroughs.