An invention from 71 years ago changed the world__Commemorating the 71st anniversary of the invention of the transistor—

Before the invention of transistors, amplifying electrical signals was mainly done using electron tubes (vacuum triodes), but due to their difficulty in fabrication, large size, high power consumption, and short lifespan, there was a constant desire to replace them with solid-state devices. In 1945, Bell Labs began researching several new materials, including silicon and germanium, to explore their potential applications. A dedicated \"Semiconductor Group\" was established, with William Shockley as its leader; its members included John Bardeen and Walter Brattain. After many failures, they finally succeeded in creating the first semiconductor transistor on this very day 71 years ago – namely, the point-contact transistor with amplification capabilities based on germanium semiconductors, as mentioned above. Shockley, Bardeen, and Brattain also received the Nobel Prize in Physics for this.

Point-contact transistor: Two gold electrodes spaced 50 μm apart are pressed against a germanium semiconductor; a tiny electrical signal enters the germanium semiconductor (base) through one of the gold electrodes (emitter), is significantly amplified, and then is output through the other gold electrode (collector). This device has a gain of 4.5 at 1 kHz. Source: Bell Labs

Bardine (left), Brattain (right), and Shockley jointly received the 1956 Nobel Prize in Physics for the invention of the transistor.

The transistor is hailed as \"the greatest invention of the 20th century,\" and its emergence laid the foundation for the development of integrated circuits, microprocessors, and computer memory. In the 1950s and 1960s, while pushing for the commercialization of transistors, Shockley helped create Silicon Valley, the region now home to a thriving electronics industry in California. The history of the invention of the transistor is very complex, involving delicate relationships among science and technology, as well as between groups and society. These days, in our daily lives, chips have become indispensable components, ranging from playing music, synthesizing voice, storing data, digital photography, GPS positioning to transmitting and processing the vast amounts of data on the Internet. Among them, there are some chips that directly or indirectly power certain products that are changing the world, thereby influencing the entire computing landscape.

The initial work was based on the metal-semiconductor structure favored by Shockley; after several failed attempts, Bardeen realized that surface defects in semiconductors had a very adverse effect, and it was necessary to find ways to \"passivate\" the surfaces (eliminate the defects). Within just a few months starting in November 1947, they made significant progress and finally achieved the first semiconductor transistor.

In fact, two entirely different types of transistors were invented during this period: in December 1947, Bardeen and Brattain invented the point-contact transistor, which involved pressing two gold electrodes spaced 50 μm apart onto a germanium semiconductor. A small electrical signal entered the germanium semiconductor through one of the gold electrodes (the “emitter”), was significantly amplified there, and then outputted through the other gold electrode (the “collector”). This device had a gain of 4.5 at 1 kHz； A month later, Shockley invented the bipolar junction transistor with a sandwich structure, consisting of N-type semiconductor layers on the outside and P-type semiconductor in the middle. However, it was not until 1950 that G. Teal and M. Sparks managed to create a germanium-based NPN junction transistor. From a practical standpoint, the production volume of point-contact transistors is extremely limited, and they cannot be considered a commercial success ； Junction transistors, on the other hand, made modern semiconductor manufacturing possible and made a significant contribution to the rise of many semiconductor companies. In 1956, Bardeen, Brattain, and Shockley were awarded the Nobel Prize in Physics for the invention of the transistor.

Starting in the 1950s, transistors began to gradually replace vacuum tubes, eventually leading to the mass production of integrated circuits and microprocessors. At first, transistors and transistorized devices were not popular because they were too expensive. But the U.S. military is very interested, as military equipment has special requirements regarding portability, reliability, and durability. For most of the 1950s, it was the support of the U.S. military that allowed the young transistor industry to survive. In 1957, the Soviet satellite Sputnik was launched into space, officially marking the beginning of the Space Race between the United States and the Soviet Union. In 1961, U.S. President Kennedy announced the goal of sending humans to the Moon by 1970. Compared to the Soviet Union, U.S. rocket technology was slightly behind, so weight reduction became even more necessary; all electronic equipment made use of transistors as much as possible. The transistor-based semiconductor industry has thus advanced by leaps and bounds. Integrated circuits became the stars of this period.