Mohamed M. Atalla (Arabic: محمد عطاالله; August 4, 1924 – December 30, 2009) was an Egyptian-American engineer, physicist, cryptographer, inventor and entrepreneur.

He made several important contributions to semiconductor technology at Bell Labs, including his development of the surface passivation process and his demonstration of the MOSFET with Kahng in 1959.

His work on MOSFET was initially overlooked at Bell, which led to his resignation from Bell and joining Hewlett-Packard (HP), founding its Semiconductor Lab in 1962 and then HP Labs in 1966, before leaving to join Fairchild Semiconductor, founding its Microwave & Optoelectronics division in 1969.

In 1972, he founded Atalla Corporation, and filed a patent for a remote Personal Identification Number (PIN) security system.

[4] Between 1956 and 1960, Atalla led a small team of several BTL researchers, including Eileen Tannenbaum, Edwin Joseph Scheibner and Dawon Kahng.

[7][17] He discovered that the formation of a thermally grown silicon dioxide (SiO2) layer greatly reduced the concentration of electronic states at the silicon surface,[17] and discovered the important quality of SiO2 films to preserve the electrical characteristics of p–n junctions and prevent these electrical characteristics from deteriorating by the gaseous ambient environment.

[7][14] For the surface passivation process, he developed the method of thermal oxidation, which was a breakthrough in silicon semiconductor technology.

[20] Atalla first published his findings in BTL memos during 1957, before presenting his work at an Electrochemical Society meeting in 1958,[21][22] the Radio Engineers' Semiconductor Device Research Conference.

"[8] The same year, he made further refinements to the process with his colleagues Eileen Tannenbaum and Edwin Joseph Scheibner, before they published their results in May 1959.

[7] Atalla then proposed that a field effect transistor–a concept first envisioned in the 1920s and confirmed experimentally in the 1940s, but not achieved as a practical device—be built of metal-oxide-silicon.

Atalla assigned the task of assisting him to Dawon Kahng, a Korean scientist who had recently joined his group.

[31][32] With its high scalability,[33] and much lower power consumption and higher density than bipolar junction transistors,[34] the MOSFET made it possible to build high-density integrated circuit (IC) chips.

With its low resistance and short transit times in the thin metallic nanolayer base, the device was capable of high operation frequency compared to bipolar transistors.

Their pioneering work involved depositing metal layers (the base) on top of single crystal semiconductor substrates (the collector), with the emitter being a crystalline semiconductor piece with a top or a blunt corner pressed against the metallic layer (the point contact).

They developed high vacuum metal film deposition technology,[43] and fabricated stable evaporated/sputtered contacts,[44][45] publishing their results in January 1963.

His "Atalla Box", a security system which encrypts PIN and ATM messages, and protected offline devices with an un-guessable PIN-generating key.

The system was designed to let banks and thrift institutions switch to a plastic card environment from a passbook program.

The Identikey system consisted of a card reader console, two customer PIN pads, intelligent controller and built-in electronic interface package.

[57] Fearful that Atalla would dominate the market, banks and credit card companies began working on an international standard.

[53] In 1972, Atalla filed U.S. patent 3,938,091 for a remote PIN verification system, which utilized encryption techniques to assure telephone link security while entering personal ID information, which would be transmitted as encrypted data over telecommunications networks to a remote location for verification.

Designed with the focus of taking bank transactions online, the Identikey system was extended to shared-facility operations.

It was consistent and compatible with various switching networks, and was capable of resetting itself electronically to any one of 64,000 irreversible nonlinear algorithms as directed by card data information.

They were worried about the fact that no useful framework for electronic commerce would have been possible at that time without innovation in the computer and network security industry.

[5] Following a request from former Wells Fargo Bank president William Zuendt in 1993, Atalla began developing a new Internet security technology, allowing companies to scramble and transmit secure computer files, e-mail, and digital video and audio, over the internet.

Its security system wrapped a secure, encrypted envelope around individual pieces of information (such as a word processing file, a customer database, or e-mail) that can only be opened and deciphered with an electronic permit, allowing companies to control which users have access to this information and the necessary permits.

[5] In 2009, he was inducted into the National Inventors Hall of Fame for his important contributions to semiconductor technology as well as data security.