The Physics of Semiconductor Devices
explanatory Essay
2178 words
The Physics of Semiconductor Devices
The purpose of this paper is to give a greater understanding of the semiconductor world, for Physics 100 students who have a little knowledge of electronics. I will cover conductors, insulators, semiconductors, and the operation of a diode and a transistor. The reason that it is important to understand these devices is the vast effect that they have had on our modern world. Our lives are filled by electronics, especially in this computerized age that we live in, and I have found that a knowledge of some electronics has greatly helped my understanding of the many electronic devices that we deal with on a daily basis.
To understand the physics of a semiconductor device it is first necessary to take a step back into basic electronics and establish a basis for this discussion. The best starting point is electricity itself. Electricity is simply electrons moving together through a conductive path, conductive meaning that it does not slow it down in any way. There are many papers and books on how electricity works and it is not the purpose of this paper to explain this but rather how electricity moves through certain materials. Every college student in America should know that electricity moves through metal wires, this is because metal conducts electricity. The most common metal used for this purpose is copper. Copper is not the only conductive material in the world, gold, silver, steel, and iron are all examples of metals that conduct electricity. However gold and silver are very expensive and copper conducts electricity better than steel and iron. Metal itself is not the only material that conducts electricity but will conduct it the easiest.
We will now discuss briefly how a copper...
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With the completion of our discussion of Ohms law this paper makes it possible to understand basic semiconductors and how they are used in small circuits. I will again stress how vast the electronics world is becoming and that this is just a small start into that world. Many books are contained on how these two components are used but if taken a small step at a time these are not difficult to understand. I hope that this can give someone a start into this world of knowledge on electricity.
References:
MacDonald, Lorne; Basic Solid State Electronic Circuit Analysis, fourth edition.
The Technical Education Press; Chico California. 2000. MacDonald, Lorne; Practical Circuit Analysis of Amplifiers.
The Technical Education Press; Chico California. 1994.
Physics, a World View; Kirkpatrick and Wheeler, fourth edition, Harcourt College Publishers, 2001.
In this essay, the author
- Explains the process of adding impure atoms to pure silicon crystals is called doping.
- Explains that the p type material is a very small band in the center of the transistor. the depletion region between the collector and the emitter is reverse biased from the base.
- Explains that the purpose of this paper is to give a greater understanding of the semiconductor world for physics 100 students.
- Explains how a diode is constructed, stating that the voltage flowing through it determines the size of the depletion region.
- Explains how diodes are used to convert ac power into dc or high speed switches in digital devices. the second semiconductor is the transistor.
- Illustrates how a simple transistor amplifier operates using ohms law, which is given by the equation v=ir.
- Explains how ohms law makes it possible to understand basic semiconductors and how they are used in small circuits.
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