Conductor Insulator &semiconductor

Quick introduction of Conductor semiconductor & insulator

1. INSULATOR CONDUCTOR SEMICONDUCTOR 191400034 Sohaib

2. Every atom wants stability, so it gains, loses or shares to complete its outermost shell so it becomes stable Sohaib

3. Insulator a material that block or retard the flow of electron. Plastic Rubber Glass

4. Insulator Atomic Structure Complete Valance Shell, 5-7 valance electron in its outermost Shell.

5. Conductor a material in which electrical charge carriers, usually electrons, move easily from atom to atom with the application of voltage or current. Aluminum Copper Graphite

6. Conductor Atomic Structure Incomplete outermost shell. 1-3 Valance Electron in it’s outermost shell.

7. Semiconductor  a material that is neither a good conductor nor a good insulator Silicon germanium P-type / N-type

8. Semiconductor Atomic Structure Incomplete outermost shell. 4 Valance Electron in it’s outermost shell.

9. Energy Band an enormously large number of energy levels closely spaced in a very small energy range constitute  energy band . Valance Band The highest energy band filled with valence electrons is called  valence band.   conduction band The lowest unfiled allowed energy band next to valence band is called  conduction band .

10. energy gap or band gap or Forbidden Band  The gap between top of valence band and bottom of conduction band in which no allowed energy levels for electrons can exist is called  energy gap or band gap . A position in which conduction band and valance band over lap each other is called overlap region , in this region electron jump from valance band to conduction band where conduction process is been occurred.

11. Thank you

12. Why gap band is called Forbidden Energy Band? the electrons do not stay in  forbidden  gap as there is no  energy  state in this region.