Who Invented the Computer? Five Guys and the Transistor

Who Invented the Computer? This is the twelfth installment in our ongoing series.

Good things, as they say, come in small packages and nothing smaller or better has ever arrived than the transistor. Considered the most important invention of the 20th century, this itty-bitty technology has literally transformed every field of industry and improved the lives of every man, woman, and child on Earth.

As with almost every great invention, transistors were born out of need in the immediate aftermath of World War II. Since 1907, the American Telephone and Telegraph Company ("AT&T") had used vacuum tubes to amplify voice signals along their lines. With regular amplification along a line, people could participate in telephone conversations over vast distances.

There was however a problem with using vacuum tubes to amplify signals: The tubes were too often unreliable, as they took time to warm up before operating. They also generated lots of heat and often burned out, costing a great deal of money to replace.

Mervin Kelly, President of Bell Laboratories, a subsidiary of AT&T, was actively searching for a sturdier and more efficient alternative to vacuum tubes. He had done some reading on the development of a new class of materials called semi-conductors and decided they had potential.

Kelly handed the problem off to the company's Solid State Physics group, a highly creative team headed by renowned physicist William Shockley. Composed of brilliant individuals from diverse scientific disciplines, the group had great chemistry. Working closely, members regularly bounced ideas and problems off of one another. They also had a reputation for "exuberant" parties and lunches.

In early 1945, Shockley designed a semi-conductor amplifier that he hoped would successfully operate on the basis of "field effect." The device consisted of a small cylinder with a thin coat of silicon mounted next to a metal plate.

Alas, Shockley's revolutionary design at first led only to repeated failures. With his field effect idea effectively stalled out, Shockley assigned fellow physicists John Bardeen — destined to become the only person to be awarded the Nobel Prize in Physics twice — and Walter Brattain to figure out what was causing all of the problems.

All wet

After almost two years, the team had still failed to come up with a working semi-conductor amplifier. Then one afternoon, Brattain was conducting a series of tests on how electrons acted on the surface of a semiconductor, investigating why the way they acted made an amplifier impossible. Because condensation would continuously build up on the silicon component of the device, Brattain realized he needed to conduct the experiment in a vacuum environment.

Rather than take the time to reset everything, Brattain took the counterintuitive move of immersing the experiment in water. He later explained that he was "just being lazy" but, to his surprise, the wet device immediately showed a slight level of amplification.

Working closely with Bardeen the duo tinkered about with additional materials soon and discovered that applying a positive electrical charge to the device gave them a larger amplification while a negative charge removed the amplification completely. They had made a working solid state amplifier — the world's first "point-contact" transistor.

Shockley, who was known to have a sensitive and easily offended personality, was delighted with their progress, but upset that he hadn't been directly involved in the discovery. Because Shockley could at times be incredibly abrasive, it's not a surprise that company attorneys left his name off the transistor patent application. The new device was called a "transistor," a combination of the ideas of "trans-resistance" and a thermistor (a temperature sensor). The name was actually suggested by fellow team member John Pierce, who wrote science fiction in his spare time.

Maintaining that the original concept for the transistor was his, Shockley would continue working in secret for two years finally developing what he called a "junction transistor." Shockley's transistor was a significant improvement over the point-contact model, as it was more durable and efficient and easier to manufacture.

Although the Bell Team would eventually split up — most agree this was due to Shockley's incessant caviling — in 1956 Shockley, Bardeen and Brattain would receive a joint Noble Prize for their contributions to physics.

Impact of transistors

AT&T knew they had hit on a huge improvement in communications and saw the U.S. military as the primary market for transistors. After additional improvements to the transistor, the company exhibited its invention to the military in 1949, expecting it to be classified "top-secret."

Much to their surprise, the military didn't move on it. The next day, the company announced the invention and was soon selling licenses for the manufacturing of transistors to other companies.

The first widespread use for transistors was in hearing aids and the worldwide fad of "transistor radios." From there the technology advanced rapidly. Its most significant leap occurred in 1959 when Mohamed Atalla and Dawon Kahng, working for Bell Labs, developed a metal-oxide semiconductor field effect transistor (MOSFET), the first truly scalable transistor and the basic building block of modern electronics.

The advantage of MOSFET was it was easily manufactured and placed into an integrated circuit — lots of tiny transistors stamped onto a single sheet of semi conductive material. It is included in virtually all modern electronics. It is the most frequently manufactured device in history — an estimated 13 sextillion (1.3 x 1022) were made between 1960 and 2018, with billions more produced each day.

MOSFET revolutionized electronics, enabling the development of unbelievably powerful computing devices at a fraction of the size and cost of earlier computers. As an example, the 1969 Moon Landing was accomplished with a mere 32,000 bits of RAM, one millionth of what we have on our cell phones today. With that much computing power in the palm of our hand, it's no wonder the transistor is considered the most important invention of the 20th century.