Ballistic transistor

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Ballistic Transistors are electronic devices currently[when?] being developed for high-speed integrated circuits, which is a set of circuits bounded on semiconductor material. They use electromagnetic forces instead of a logic gate, a device used to perform solely on specified inputs, to switch the forces of electrons. The unique design of this transistor includes individual electrons bouncing off of wedge-shaped obstacles called deflectors.[1] Initially impelled by the circuits electric field, electrons proceed on their respective paths via this electromagnetic deflection. Electrons are then able to travel without being scattered by atoms or defects thus producing an increased transit time.[2] With an increased transit time, the ballistic transistor will be able to produce longer and more effective results than the standard transistor today.


A ballistic transistor would be significant in acting as both a linear amplifier and a switch for current flow on electronic devices. A transistor used as a linear amplifier helps heighten a signal on a device. Additionally, a transistor used as a switch for current flow helps maintain digital logic and memory on devices. A transistor's switching speed greatly affects how fast charge carriers-typically electrons-can cross from one region to the next. For this reason, researchers want to use ballistic action to improve the charge carrier's traveling time and speed.[2] A standard transistor is used to amplify electronic power and signals. However, ballistic transistors will be able to fulfill its purpose and last longer than standard transistors because of its continuous flow of electrons. With this, the transistors should also be able to withstand immense amounts of heat, or rather perform faster in order to avoid drawbacks.[1]


One advantage of the ballistic transistor is that because such device will use very little power, it will create less heat. Having produced less heat, it will be able to withstand a longer duration and speed. Thus, it will be easier to incorporate into a variety of technology. This design will also reduce electrical noise that come from the electronic devices.[1] With an increased speed, another advantage of the transistor is that it will be beneficial in both aspects of linear amplifier and switch. The signal on a device would massively increase as well as its memory because the transistor will be able to withstand more than the standard chips.[2] Additionally, the size of an ideal ballistic transistor is going to be significantly smaller than the standard transistor. The reduced size helps with the precision of electron movement, thus eliminating any error of fluctuations of random scattering and collision.[3]


The goal of many laboratories around the world is creating semiconductors that can operate faster than current technology.[2] Specifically, electrons within the transistor will be able to actively travel with no collisions.[4] Research shows that with low velocities come unstable electron flow.[4] Thus, when the electrons have a high velocity and long distance over which they can remain ballistic, then they will be able to travel through semiconductor material without being scattered. Currently, the silicon Metal Oxide Semiconductor Field-Effect Transistor (MOSFET) is the main and leading research circuit. However, researchers predict that finding the ideal semiconductor will increase the dimensions of the transistor, even greater than the current silicon.[2] In the early 1960s, there has been speculation that replacing the silicon with metal would increase the energy barrier between electrons and the semiconductor. Scientists now are also currently trying to improve two aspects of the standard transistor. The first is the common emitter, which is an amplifier used as a reference point between the point and collector. Scientists are trying to reduce the width of the emitter, in belief that it would increase the speed of electrons. The second is the base of the transistor. Scientists are trying to make the base as thin as possible, even as thin as 70 nanometers, so that there is a less travel length and time for the electrons through the base.[2] When a device exceeds its permitted power consumption, there will be a leakage current. The ideal transistor should maintain a low to no leakage current. In order for this to happen, the device will have to operate in low temperatures, again meaning that it will have to use very little power.[3] A prototype of the transistor has recently been created by the Cornell Nanofabrication Facility.[1]

An earlier vacuum tube device called a beam deflection tube provided a similar functionality based on a similar principle.


  1. ^ a b c d Sherwood, Jonathan. "Radical 'Ballistic Computing' Chip Bounces Electrons Like Billards". 
  2. ^ a b c d e f Bell, Trudy E. (February 1986). "The Quest for Ballistic Action". 2. 23: 36–38. doi:10.1109/mspec.1986.6370997. 
  3. ^ a b Natori, Kenji (6 July 1994). "Ballistic metal-oxide semiconductor field effect transistor". Journal of Applied Physics. 76 (8): 4879. doi:10.1063/1.357263. 
  4. ^ a b Dyakonov, Michael; Michael Shur (11 October 1993). "Shallow Water Analogy for a Ballistic Field Effect Transistor: New Mechanism of Plasma Wave Generation by dc Current". Physical Review Letters. 71 (15): 2465–2468. Bibcode:1993PhRvL..71.2465D. doi:10.1103/PhysRevLett.71.2465.