Deep Dive: E6E01
The correct answer is B: Higher electron mobility. Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies is that it has higher electron mobility. Higher electron mobility allows faster operation at high frequencies. For amateur radio operators, this is important for semiconductor knowledge. Understanding this helps when selecting semiconductors.
Why Other Answers Are Wrong
Option A: Incorrect. Higher noise figures isn't an advantage - GaAs has higher electron mobility. Higher noise isn't the reason. Option C: Incorrect. Lower junction voltage drop isn't the reason - GaAs has higher electron mobility. Junction voltage isn't the reason. Option D: Incorrect. Lower transconductance isn't the reason - GaAs has higher electron mobility. Lower transconductance isn't the reason.
Exam Tip
GaAs useful at UHF+ = higher electron mobility. Think 'G'aAs = 'G'ood 'A't high frequency (higher mobility). Higher electron mobility allows faster operation at high frequencies. Not higher noise, not lower junction voltage, not lower transconductance - just higher electron mobility.
Memory Aid
GaAs useful at UHF+ = higher electron mobility. Think 'G'aAs = 'H'igher 'M'obility. Higher electron mobility allows faster operation at high frequencies. Important for semiconductor knowledge.
Real-World Example
Gallium arsenide (GaAs) for semiconductor devices operating at UHF and higher frequencies: It's useful because of higher electron mobility. Electrons move faster in GaAs, allowing devices to operate at higher frequencies. This is the reason - higher electron mobility.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E6E
Reference: 2024-2028 Question Pool · E6 - Circuit Components
Key Concepts
Verified Content
Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E6E topic.