P-Type Semiconductor Basics
If we introduce a "Trivalent" (3-electron) impurity into crystal structure, like Boron, Aluminium, or Indium, just three valence electrons are available in outermost covalent bond meaning that the fourth bond cannot be formed. Thus, a complete connection is not possible, providing the semiconductor material an abundance of the positively charged carriers called as "holes" in the structure of crystal. As there is a hole a neighboring free electron is attracted to it and will try to move into hole to fill it. Although, the electron filling the hole leaves another hole behind it as it moves. This then attracts another electron which in turn generates another hole behind, and so forth giving the appearance that holes are moving as a positive charge through the crystal structure (this is termed as conventional current flow). As each impurity atom generates a hole, trivalent impurities are generally called as "Acceptors" as they are continually "accepting" the extra electrons.
Boron (symbol B) is often used as a trivalent additive as it has only five electrons arranged in three shells around the nucleus. Addition of the Boron causes conduction to consist mainly positive charge carrier's results in the "P-type" material and positive holes are called as "Majority Carriers" while the free electrons are called as "Minority Carriers". Then a semiconductor is P-type when its acceptor density is greater than the donor density of it. Thus, a P-type semiconductor has more holes than the electrons.
The diagram drawn above shows the structure and lattice of the acceptor impurity atom Boron.
Email based Electronics Devices and circuits assignment help - homework help at Expertsmind
Are you searching Electronics Engineering assignment help expert for help with P-type Semiconductor Basics questions? P-type Semiconductor Basics topic is not easier to learn without any external help? We at www.expertsmind.com offers free lecture notes for Electronics Devices and circuits assignment help and Electronics Devices and circuits homework help. Live tutors are available 24x7 hours for helping students in their P-type Semiconductor Basics related problems. We provide step by step P-type Semiconductor Basics question's answers with 100% plagiarism free content. We prepare quality content and notes for P-type Semiconductor Basics topic under Electronics Devices and circuits theory and study material. These are avail for subscribed users and they can get advantages anytime.
Why Expertsmind for assignment help
- Higher degree holder and experienced experts network
- Punctuality and responsibility of work
- Quality solution with 100% plagiarism free answers
- Time on Delivery
- Privacy of information and details
- Excellence in solving electronics engineering questions in excels and word format.
- Best tutoring assistance 24x7 hours