10/05 Manga Electricity Questions

Please answer the following on the blog:


1. What is an example of a semiconductor device?


LED (LIGHT EMITTING DIODE)2. Why is silicon used in the manufacture of semiconductors? 

• LOW MATERIAL COST
• TEMPERATURE RANGE
• SIMPLE PROCESSING

3. Discuss the difference using an example of the difference between and N-type and P-type semiconductor.

SEMICONDUCTOR MATERIAL IS USEFUL, BECAUSE THEIR BEHAVIOR CAN BE MANIPULATED THROUGH THE PROCESS KNOWN AS DOPING ( THE INTRODUCTION OF IMPURITIES TO A EXTREMELY PURE(INTRINSIC) SEMICONDUCTOR, FOR THE SAKE OF MODULATING ITS ELECTRICAL PROPERTIES. THE MANIPULATED SEMICONDUCTORS ARE KNOWN AS EXTRINSIC SEMICONDUCTORS. 

P-TYPE:

• DOPED SEMICONDUCTOR CONTAINING EXCESS HOLES
• P = POSITIVE FOR HOLES

N-TYPE:

• DOPED SEMICONDUCTOR CONTAINING EXCESS FREE ELECTRONS
• N = NEGATIVE FOR ELECTRONS

COLLECTIVELY ELECTRONS AND HOLES ARE KNOWN AS CHARGE CARRIERS. "P" OR "N" IS THE SIGN OF THE CHARGE OF THE MAJORITY MOBILE CHARGE CARRIERS.

4. In your own words describe what a diode does and the role of N and P type semiconductors.

• MADE FROM A P-N JUNCTION
• DEPLETION REGION MADE AT JUNCTION
• CURRENT CONDUCTION IS RESERVED DUE TO LACK OF MOBILE CHARGE CARRIERS
• WHEN DEVICE IS FORWARD BIAS
• CONNECTED W/ P SIDE AT HIGHER ELECTRICAL POTENTIAL THAN N
• DEPLETION REGION IS DIMINISHED
• INCREASE CONDUCTION
• 
  
• WHEN DEVICE IS REVERSED BIAS
• SMALL CURRENT ACHIEVED
• DEPLETION REGION EXPAND

5. What is rectification?

ELECTRICAL DEVICE THAT CONVERTS ALTERNATING CURRENT AC, WHICH SOMETIMES REVERSES DIRECTION, TO DIRECT CURRENT DC, WHICH ONLY FLOWS IN ONE DIRECTION

6. What causes color in an LED? Give and example of what causes a particular color.

• 2-LEAD SEMICONDUCTOR LIGHT SOURCE
• P-N JUNCTION
• EMITS LIGHT WHEN ACTIVATED
• ELECTROLUMINESCENCE (THE EFFECT OF VOLTAGE APPLIED TO THE LEADS, ELECTRONS COMBINING WITH ELECTRON HOLES, AND RELEASING ENERGY IN THE FORM OF PHOTONS. 
• THE COLOR OF THE LIGHT CORRESPONDS WITH THE ENERGY OF THE PHOTON, AND IS DETERMINED BY THE ENERGY BAND GAP OF THE SEMICONDUCTOR

7. What is the relationship between base current and collector current in a transistor?


BASE CURRENT : CURRENT FLOWS FROM THE BASE TO THE EMITTER

COLLECTOR CURRENT : AS THE BASE CURRENT FLOWS, CURRENT FROM THE COLLECTOR BEGINS TO FLOW TO THE EMITTER AS WELL.

*COLLECTOR CURRENT BECOMES > THAN BASE CURRENT


8. What are the advantages of a transistor over a switch? 

TRANSISTORS

• NO CONTACT (LESS WEAR & TEAR)
• CAN BE MANIPULATED MUCH EASIER
• FASTER RESPONSE
• MORE CONTROL