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Germanium
Germanium (Ge) is a metalloid semiconductor. It is commonly used in optics and electronic circuitry.
542 Questions
What is the threshold voltage of silicon and germanium?
In semiconductor uses, such as diodes and transistors, the forward voltage drop for Silicon (Si) is a little less than 0.7 volts, while the FVD for Germanium (Ge) is about 0.3 volts.
Why silicon is preferred over germanium as a semiconductor?
The oxide of silicon is a stable insulating insoluble solid, making it possible to integrate the metal interconnects in planar layers over the semiconductor.
The oxide of germanium is unstable and soluble in water, making it necessary to connect the integrated components with individual wires which is far too labor intensive and is also impractical for integration levels beyond MSI. Texas Instruments made some prototype SSI germanium ICs this way in 1958 and 1959 but abandoned the process when they licensed Fairchild's planar silicon IC process.
No ICs are made of germanium now, only discrete transistors and diodes.
Some work has been done on ICs made of silicon-germanium alloy, but I am not sure of the current status.
Was Germanium used in transistors?
Yes, germanium was the only material used in transistors from when they were invented in 1947 until 1954 when the first successful silicon transistor was made.
However the use of germanium still dominated transistors until the silicon mesa transistor was made commercially available by Fairchild Semiconductor in 1958. Development of the silicon planar transistor by Fairchild Semiconductor the next year ultimately made the integrated circuit possible.
While almost all transistors today are silicon, there are still uses for germanium transistors so a few types are still made.
Why silicon is preferred over germanium in the fabrication of integrated circuits?
The invention of the planar process by which most IC devices are fabricated relies on the gas phase diffusion of dopants to produce N-type and P-type regions, but also on the ability of silicon dioxide to mask these diffusion processes and passivate the chip surface eliminating the need for hermetic packaging. Silicon is unique in its ability to be oxidized to produce a stable insulating coating.
Germanium dioxide is crumbly and water soluble, making it impossible to use in this process. While the first IC made used germanium, it had to be handwired which would have made them prohibitively expensive to produce and much larger than even the early silicon ICs.
What is the normal phase for the element neon?
Neon, an inert gas, is a gas at non-cryogenic temperatures. A link is provided to the Wikipedia article on neon.
What is a substitute for a germanium diode?
There is no exact substitute for a germanium diode, except another germanium diode.
However if the only concern is to get a lower forward voltage drop than that of a silicon diode (0.7V), then a schottky barrier diode may be a suitable replacement as its forward voltage drop (<0.1V) is even lower than that of a germanium diode (0.2V).
How did Mendeleev place germanium on the periodic table?
Mendeleev was able to predict the properties of the yet unknown element (Germanium) by the properties of the surrounding known elements on his periodic table of the elements. Predicting properties such as reactivity, density, atomic mass, etc., he knew where the undiscovered element would be placed.
Why germanium and silicon are not preferred in LEDs?
A: Because the element has different property as gallium arsenide.
Why germanium controlled rectifiers are not used instead of silicon controlled rectifiers?
The first solid state four layer thyristors made were indeed made of germanium and therefor could be called "germanium controlled rectifiers" (although this name was never used in the literature, they were just called thyristors). But when it became practical in the early 1960s to make solid state devices using silicon, the higher operating junction temperature and the ability to self passivate junctions in silicon devices soon made germanium devices obsolete especially for high power applications (which include many of the applications of solid state four layer thyristors).
The term thyristor was coined originally for these devices as they were seen as a solid state version of the gas filled thyratron tube. The idea of calling them "controlled rectifiers" only came years later when silicon had replaced germanium for most purposes in solid state devices.
If diode works properly in 0.7volts than why we you use ideal diode and practical diode?
In theory A diode clamps 0.7 volts across it but in practice the number is not exactly 0.7 volts because it can not be controlled. This is only the case with Silicon Diodes (clamping 0.7 volts), as Germanium ones, ideally clamp 0 Volts, but in practice it is not exactly Zero.
Basically, in practice it is not exactly 0.7 volts but when doing theory one assumes it to be 0.7volts for ease of operation.
How might a gallium chip compare with a germanium chip?
Gallium is a metal, not a semiconductor. You cannot build a transistor or even a diode with a piece of metal, forget an IC chip containing several transistors.
To create a gallium based semiconductor, it must be ALLOYED with one or more of the following elements: nitrogen, phosphorus, arsenic, or antimony. The simplest semiconductor alloys are: gallium nitride, gallium phosphide, gallium arsenide, and gallium antimonide. Examples of other semiconductor alloys are: gallium nitride phosphide, gallium phosphide arsenide, etc. (these are used in some types of LEDs).
The most common gallium alloy semiconductor for making transistors and IC chips is gallium arsenide. Compared to both silicon and germanium, transistors made of gallium arsenide are significantly faster, and additional speed can be obtained by using nonsaturating logic circuits like ECL.
What is the history of germanium diode?
Germanium point contact diodes were first created and used during World War 2 as detectors in microwave RADAR systems, as the vacuum tubes available at that time did not operate at microwave frequencies.
Shortly after World War 2 germanium junction diodes were created.
What do Lead tin germanium silicon carbon have in common?
They are all in the same group (column) of the Periodic Table and have the same number of valence electrons (4).
Why is LED not made of silicon or germanium?
Silicon and Germanium are not used to make LEDs.
- They are opaque to visible light
- They have the wrong type of band gap (direct instead of indirect).
LEDs are made with binary semiconductors, like:
- Indium Gallium Nitride
- Silicon Carbide
- Indium Phosphide
- Gallium Indium Arsenide Nitride
- Indium Gallium Aluminum Phosphide
- etc.
The density of germanium (Ge) is around 5.323 grams per cubic centimeter at room temperature.
Is germanium a non metal or metal or metalloid?
Germanium is a metalloid. It exhibits properties of both metals and non-metals, making it a semiconductor commonly used in electronic devices.
Never.
All the germanium on earth was produced in supernova explosions more than 6 billion years ago.
What is the chemical formula for germanium sulfite?
The chemical formula for germanium sulfite is Ge(SO3)2
What the chemical formula for germanium and sulfur?
Ge is Germanium, S is Sulfur, Germanium (di)sulfide is GeS2
Germanium disulfide refers to the chemical compound with the formula GeS2. It is a colourless white crystalline material, which melts at roughly 800 °C.
Germanium sulfide was the first germanium compound found by Clemens Winkler during the analysis of argyrodite. The fact that germanium sulfide is not soluble in acidic water made it possible for Winkler to isolate the new element from the other elements.
