What is the role of a p-n junction in a semiconductor device?
Practice Questions
Q1
What is the role of a p-n junction in a semiconductor device?
To increase resistance
To create a depletion region
To enhance thermal conductivity
To reduce current flow
Questions & Step-by-Step Solutions
What is the role of a p-n junction in a semiconductor device?
Step 1: Understand that a p-n junction is formed when two types of semiconductor materials are joined together: p-type (positive) and n-type (negative).
Step 2: Recognize that the p-type semiconductor has extra holes (positive charge carriers) and the n-type has extra electrons (negative charge carriers).
Step 3: When these two materials are joined, electrons from the n-type region move to fill holes in the p-type region, creating a region with no charge carriers called the depletion region.
Step 4: The depletion region acts as a barrier that controls the flow of electrical current, allowing current to flow in one direction (forward bias) but not the other (reverse bias).
Step 5: This property is crucial for the functioning of devices like diodes (which allow current to flow in one direction) and transistors (which can amplify or switch electronic signals).
