Views:6 Author:Site Editor Publish Time: 2018-09-20 Origin:Site
Transistors are considered to be the greatest inventions in electronic technology in the 20th century, setting off a microelectronics industry revolution and laying the foundation for a modern civil society. And since its inception, it has facilitated the indissoluble bond of tungsten.
The invention of the transistor dates back to 1929, when the engineer Lilian Feder had obtained a patent for a transistor. However, limited to the state of the art at the time, the materials used to make such devices did not reach sufficient purity, making such transistors impossible to manufacture. Until 1945, Bell Labs was founded with WB Shockley as the team leader, experimental physicists WH Brattain and GL Pearson, and physical chemist R. Gibney. And circuit expert H. Moore, and theoretical physicist J. Bardeen and other semiconductor research groups.
Shortly after the formation of the research team, members shifted their research focus from the development of field-effect amplifiers to the fundamental theory of semiconductors, the study of surface states. The surface state problem is the basis for advancing the "field effect amplifier" experiment. After more than a year of trial and error, in September 1947, the research team finally confirmed that the surface state effect did exist. Further research revealed that a liquid containing positive and negative ions such as water was injected between the electrode plate and the surface of the silicon crystal, and the surface state effect was enhanced or weakened by applying a voltage.
On November 21, 1947, Badin proposed to Bratton to start a semiconductor amplifier development experiment. The two of them conducted experiments on the same day and observed a weak amplified current signal in the output loop. But their amplifying devices have almost no voltage gain and can only operate in an ultra-low frequency range of no more than 10 Hz, while a utility amplifier must be able to amplify an input signal of several kilohertz.
On December 11, 1947, Gibney provided an N-type bract that had an oxide layer on the surface (to replace the electrolyte), and deposited five small gold particles on the oxide layer. Bratton made a small hole in the gold grain, using tungsten wire to pass through the small hole and the oxide layer to insert the germanium crystal as an electrode. I hope to change the tungsten wire electrode and the crucible by changing the voltage between the gold grain and the germanium crystal. Conductivity between crystals. As a result, it was found that the electric resistance between the gold particles and the ruthenium crystal was small, that is, the oxide layer did not function as an insulation.
Despite this, Bratton decided to do a few experiments to try. In one experiment, Bratton accidentally added a negative voltage to the tungsten wire, adding a positive voltage to the gold particles, and did not expect a signal at the output that reversed the change at the input. The result of the preliminary test is that the voltage amplification factor is 2 and the upper limit frequency is up to 10 kHz. This means that it is not necessary to make an oxide film on the surface of the germanium crystal, and the gold particle and the germanium crystal surface can be directly contacted to obtain a good response frequency.
Badin is keenly aware that a new physical phenomenon, completely different from the addition of electrolyte, has emerged at the interface between the gold particles and the ruthenium crystal. Based on this, he redesigned a set of experiments. The key to the experiment was to make the tungsten wire contact on the surface of the germanium crystal as close as possible to the metal electrode. Badin’s calculations point out that the distance between the two should be on the order of 50 microns. Bratton and the technician quickly produced a set of experimental devices that met the requirements of Badin, and on the afternoon of December 16, they performed an improved first experiment with Badin. In this experiment, they achieved 1.3 times the output power gain and 15 times the output voltage gain. Therefore, some scholars have argued that this day should be determined as the invention day of the transistor. Tungsten and transistors have also formed this indissoluble bond.
A week later, on December 23, the semiconductor research team led by Shockley demonstrated the audio amplification experiment for Bell's supervisor using an experimental device containing the newly invented solid-state amplifier. This is an audio amplification experiment without a tube. The experiment was as successful as one expected. Later, the research team named the solid-state amplifier "transistor" and translated it into "transistor" in Chinese. Since such a transistor is mainly composed of two wires in point contact with a semiconductor, it is called a two-pole point contact transistor.
On June 17, 1948, the patent agent of Bell Telephone Laboratories completed the patent declaration procedure for point contact transistors. On June 23, Bell showed the US military representative the transistor demonstration device he invented and was finally allowed to publicize it. At the same time, Shawley and Pearson, Buding and Bratton collaborated on a series of essays on the theory of how transistors work and how they work. After the preparations were completed, Bell held a press conference in the headquarters building on June 30, publicizing the news that the world's first transistor was born.
Since then, the fire of the stars of the transistor that was ignited by Buding and Brighton in 1947 has begun to form a prairie. At present, two-dimensional materials such as tungsten disulfide and tungsten diselenide, which have excellent properties such as electricity, optics, plasma, electrochemistry and electrocatalysis, have become the new favorite of the next generation of computer transistors.