Do they still make germanium transistors?

Most germanium transistor production ceased in the 1970s in favor of silicon which are more stable, consistent, have higher gain, and lower leakage.

Why C is not used as a semiconductor?

Carbon is a non-metal, and non-metals weakly conduct electricity. This is because the atoms or the molecules in carbon are closely packed to each other. Even though carbon lies in the same group of periodic table as germanium and silicon, it is not a pure or an intrinsic semiconductor.

Why is germanium used in transistors?

Germanium played an essential role in the development of the first transistor and its usefulness as a semiconductor thus became recognized. The superior electron and hole mobility of germanium as well as its low melting point has spurred much research into replacing current silicon based devices with germanium.

Why is silicon rather than carbon or germanium used in the semiconductor industry?

Silicon has seen extensive use as a semiconductor material since the 1950s. The most abundant element on earth after carbon, silicon has four valence electrons and melts at a higher temperature than germanium (1,414 degrees Celsius in comparison to germanium’s 938.3 degrees Celsius).

Why does it matter whether a transistor is germanium or silicon?

germanium has a low melting point and germanium transistors have much less tolerance for high temperatures. The forward voltage drop of a germanium junction is lower than for silicon. This can be an advantage in some critical applications.

How do you know if a transistor is silicon or germanium?

The main difference between germanium and silicon transistors in switching circuits, be they either PNP or NPN transistors is that VBE for small germanium is about 0.3 volts whilst those of silicon are about 0.7 volts.

Why only silicon and germanium are used as semiconductors?

Both silicon and germanium are semiconductors and contains 4 valence electrons. This means that both of them exhibit properties of metals and non-metals. Silicon is cheaper and can be used at higher temperatures to conduct heat and electricity. On the other hand, germanium also has 4 valence electrons like silicon.

Is germanium a semiconductor?

Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard-brittle, grayish-white metalloid in the carbon group, chemically similar to its group neighbors silicon and tin. Pure germanium is a semiconductor with an appearance similar to elemental silicon.

Why germanium is not used in transistors?

The structure of Germanium crystals will be destroyed at higher temperature. However, Silicon crystals are not easily damaged by excess heat. Peak Inverse Voltage ratings of Silicon diodes are greater than Germanium diodes.

Why did silicon transistors replace germanium transistors?

Later, Fairchild Semiconductor developed a version which was entirely flat — these were called “planar” transistors. 1958: Germanium transistors broke down at high temperatures, so they were eventually replaced by silicon transistors.

Why transistors made of silicon is preferred over the germanium semiconductor material?

At room temperature, Silicon crystal has fewer free electrons than Germanium crystal. However, Silicon crystals are not easily damaged by excess heat. Peak Inverse Voltage ratings of Silicon diodes are greater than Germanium diodes. Si is less expensive due to the greater abundance of element.

Why germanium is not used in SCR?

Ability to withstand at high temperature: silicon crystals have capability to withstand at higher temperature compare to germanium crystals . So if leakage current is produced in SCR it heats up the device then silicon crystals can withstand but not germanium crystals.

What is the base material of a transistor?

Typically a thin wafer of Germanium was used for the base of the transistor. The emitter and collector were made by diffusing two pellets of Indium (a trivalent material, having three electrons in their valence shell) into either side of a wafer of N type base, as shown in Fig 3.2.1.

Why can’t we make transistors out of graphene?

The problem is that with current technology it is impossible to build semiconductor transistors, and this is so because as graphene is superconducting, it would not have an “off” state.

How does germanium increase the strength of a transistor?

When electric current is applied to one contact, the germanium boosts the strength of the current flowing through the other contact. William Shockley improved upon their work creating a junction transistor with “sandwiches” of N- and P-type germanium.

How did transistors transform the world of electronics?

Transistors transformed the world of electronics and had a huge impact on computer design. Transistors made of semiconductor s replaced tubes in the construction of computers.