The Key Players
2. Pioneers of the Field Effect
While a single inventor is elusive, three names consistently pop up in the MOSFET origin story: Julius Edgar Lilienfeld, Oskar Heil, and Mohamed M. Atalla (along with Dawon Kahng). Let's take a closer look at their individual contributions to the development of this groundbreaking transistor.
Julius Edgar Lilienfeld, in 1925, patented what's considered the first field-effect transistor concept. He envisioned a device where an electric field could control the conductivity of a semiconductor material. Though his patents described the idea, he didn't actually build a working prototype. Think of him as the architect who drafted the blueprint, even if the building itself wasn't constructed at the time.
Oskar Heil, in 1934, patented a similar device in Europe. Like Lilienfeld, Heil's work was theoretical and didn't result in a functional transistor. However, both Lilienfeld and Heil independently conceived the crucial principle of using an electric field to modulate current flow in a semiconductor — a foundational concept for the MOSFET.
Now, for the real breakthrough. In 1959, Mohamed M. Atalla and Dawon Kahng at Bell Labs fabricated the first working MOSFET. This is the design that truly unlocked the potential of the field-effect transistor. Atalla's work on silicon surface passivation was essential to creating a stable and reliable device. Kahng then worked to construct the physical architecture. Without this step, earlier devices could not be fabricated properly.
