Research Work# 1
Macalalad, Jp S. July 2,2013
Ceit17-301A
Contents
I. Semiconductor
A. Characteristics
B. Properties
II. The PN Junction Diode
A. Characteristics
B. Operation
C. Application
III. Zener
IV. Light Emitting Diode (LED)
V. Photo Diode
VI. Varactor Diode
VII. Tunnel Diode
VIII. IR Emitter
IX. Rectifier
Semiconductor
A semiconductor, such as silicon, has properties somewhere between those of a conductor and an insulator. The ability of a semiconductor to conduct electricity can be changed dramatically by adding small numbers of a different element to the semiconductor crystal. This process is called doping. Early experiments showed that an electric current through a semiconductor was carried by the flow of positive charges as well as negative charges (electrons).
Semiconductors Material: Ge, Si, and GaAs
The construction of every discrete (individual) solid-state (hard crystal structure) electronic device or integrated circuit begins with a semiconductor material of the highest quality
Semiconductors are a special class of elements having a conductivity between that of a good conductor and that of an insulator
In general, semiconductor materials fall into one of two classes: single –crystal and compound. Single –crystal; semiconductor such as gallium arsenide (GaAs), cadmium sulfide (CdS), gallium, nitride (GaN), and gallium arsenide phospide (GaAsP) are constructed of two or more semiconductor materials of different atomic structures.
The three semiconductors used most frequently in the construction of electronic devices are Ge, Si and GaAs.
In the first few decades following the discovery of the diode in 1939 and the transistor in 1947 germanium was used almost exclusively because it was relatively easy to find was available in fairly large quantities. It was also relatively easy to refine to obtain very high levels of purity , an important aspect in...