History - field-effect transistor, Electrical Engineering

History - Field-Effect Transistor:

The principle of field-effect transistors was very first patented by Julius Edgar Lilienfeld in the year 1925 and by Oskar Heil in the year 1934, but practical semi-conducting devices (the JFET, junction gate field-effect transistor) was just only developed much later after the transistor effect was seen and described by the team of William Shockley at Bell Labs in the year 1947. The MOSFET (metal-oxide-semiconductor field-effect transistor) that largely superseded the JFET and had a more profound effect on electronic development was very first planned by Dawon Kahng in 1960.

Terminals

887_History - Field-Effect Transistor.png

Figure: Cross section of an n-type MOSFET

All FETs comprises a gate, drain, and source terminal which correspond roughly to the base, collector, and emitter of BJTs. Apart from the JFET, all FETs as well have a fourth terminal called the body, base, bulk, or substrate. This fourth terminal works to bias the transistor into operation; it is seldom to make non-trivial make use of the body terminal in circuit designs, but its existence is significant when setting up the physical layout of an integrated circuit. The size of the gate, length L in the figure, is the distance in between the source and drain. The width is the extension of the transistor, in the figure perpendicular to the cross section. Commonly the width is much larger than as compared to length of the gate. A gate length of 1µm limits the upper frequency to approximately 5 GHz, 0.2µm to approximately 30 GHz.

Posted Date: 1/11/2013 4:47:15 AM | Location : United States







Related Discussions:- History - field-effect transistor, Assignment Help, Ask Question on History - field-effect transistor, Get Answer, Expert's Help, History - field-effect transistor Discussions

Write discussion on History - field-effect transistor
Your posts are moderated
Related Questions
Q. Consider a reverse-biased diode with a source voltage VB in series with a load resistance RL. Write the KVL equation for the circuit.

how can i calculate that is following signal is periodic or not? X[n]= ?_(k=-8)^8¦?{d[n-4k]-d[n-1]-4k]}?

Q. What are the basic operations of  MOSFET? The gate to source voltage is set to zero volts by the direct connection from one terminal to the other,and a voltage Vds is applie

How does Expert system works? System uses a rule base and an inference engine together to simulate human reasoning whenever analysing a problem and arriving at a conclusion. To

Q What is a clipper? Describe the operation of a biased clipper and combination clipper. The circuit with which the waveform is shaped by removing (or clipping) a portion of th

RST Restart Instructions Restart instructions  are one byte call instructions. Called location for each restart instruction is  predefined on page 0 ( read only memory). They

how to make a underwater propulsion system?

A flyback converter is to be designed so that it operates in continuous "current" (flux) mode with a duty cycle of D = 0.45 when input voltage V s = 48 V, output voltage V o = 30

Distribution Transformers 1. Augmentation/Addition of Distribution Transformers Distribution transformers have to be augmented by installing additional transformers or in

A heater element is made of nichrome wire having resistivity equal to 100 × 10 -8 ohm-m. The diameter of the wire is 0.4mm. Calculate the length of the wire required to get a resi