Question

In a transistor, doping level in base is increased slightly, the collector current and base current respectively

• A. increases slightly, decreases slightly
• B. decreases slightly, increases slightly
• C. increases slightly, increases slightly
• D. decreases slightly, decreases slightly

Hint:

Higher base doping increases recombination, reducing collector current but increasing base current.

Answer 1

The Correct Option is B

Step 1: Understand the role of base doping.
The base region of a transistor is lightly doped to allow maximum charge carriers to pass into the collector region.
Step 2: Effect of increased base doping.
When base doping is increased slightly, recombination of charge carriers in the base increases.
Step 3: Effect on collector current.
Due to increased recombination, fewer charge carriers reach the collector, hence collector current decreases slightly.
Step 4: Effect on base current.
Increased recombination requires more carriers to be supplied to the base, so base current increases slightly.