In the world of microelectronics companies, STM stands for STMicroelectronics.

Formerly known as "SGS-Thomson", they are a French-Italian multinational company who are the number 1 supplier of MPEG decoder chips for set-top boxes, amongst many other things. Their huge product portfolio includes discrete components, ASSP's for a wide range of applications and a family of microcontrollers and associated IP.

As a footnote: They also bought Inmos, a semiconductor company set up by the British government in the late 70's and, rather short-sightedly IMO, sold a few years later.

A Scanning Tunneling Microscope; a microscope that uses the phenomenon of quantum tunneling to map the electron surface of a material. Particularly useful if you want to "see" the configuration of a material's surface or do cool things like manipulate individual atoms. The classic examples are the quantum corral and the smallest IBM logo in the world. See also: Scanning Tunneling Microscopy, AFM (Atomic Force Microscope), SEM (Scanning Electron Microscope), LEED (Low Energy Electron Diffraction).
