Microfabrication

Synthetic detail of a micromanufactured integrated circuit through four layers of planarized copper interconnect, down to the polysilicon (pink), wells (greyish) and substrate (green)

Microfabrication is the process of fabricating miniature structures of micrometre scales and smaller. Historically, the earliest microfabrication processes were used for integrated circuit fabrication, also known as "semiconductor manufacturing" or "semiconductor device fabrication". In the last two decades, microelectromechanical systems (MEMS), microsystems (European usage), micromachines (Japanese terminology) and their subfields have re-used, adapted or extended microfabrication methods. These subfields include microfluidics/lab-on-a-chip, optical MEMS (also called MOEMS), RF MEMS, PowerMEMS, BioMEMS and their extension into nanoscale (for example NEMS, for nano electro mechanical systems). The production of flat-panel displays and solar cells also uses similar techniques.

Miniaturization of various devices presents challenges in many areas of science and engineering: physics, chemistry, materials science, computer science, ultra-precision engineering, fabrication processes, and equipment design. It is also giving rise to various kinds of interdisciplinary research.[1] The major concepts and principles of microfabrication are microlithography, doping, thin films, etching, bonding, and polishing.

Simplified illustration of the process of fabrication of a CMOS inverter on p-type substrate in semiconductor microfabrication. Each etch step is detailed in the following image. The diagrams are not to scale, as in real devices, the gate, source, and drain contacts are not normally located in the same plane.
Detail of an etch step.
  1. ^ Nitaigour Premchand Mahalik (2006) "Micromanufacturing and Nanotechnology", Springer, ISBN 3-540-25377-7