Light Emitting Diode (LED) was developed in the laboratory in 1950 and was developed by

HP started commercial mass production. Early LED lights had only monotonous dark red electronic indicator products, but in 1992

Japanese scholar Shuji Nakamura (Shuji Nakamura), who worked in Nichia, <Note 1> Breakthrough in blue LED

After the technical obstacles, the colors gradually enriched, the brightness gradually increased, and the display (Display),

Various package types such as surface mount type (SMD) penetrate into all aspects of life.

2. The principle, characteristics and structure of semiconductor diodes

01‧Principle of semiconductor diode

A‧From the perspective of the periodic table, the IA elements (the leftmost side of the periodic table) are "filled up" electrons

An electron is placed outside the orbital <Note 2>. This electron is bound by the nucleus very little, so it is easy to form

+1 valence ion, that is, the elements of this group are highly conductive. Looking to the right again, group IIA elements, IIIA

Due to the gradual increase of the positive charges in the peripheral electrons and the nucleus of the group elements, the attraction to the electrons also gradually increases.

Plus, this effect makes the atoms gradually show a stable state, until the eighth group element on the far right is the most stable

Passive gas, and the so-called semiconductors are all elements of the third, fourth, and fifth groups in the IA <super high conductor> to the eighth group <non-conductor>.

Among them, "silicon" and "germanium" of group IV A are the most typical semiconductor materials, and because silicon is easy to obtain and easy to form an oxide film

Characteristics, so the current semiconductor industry uses silicon as the main raw material.