Which of the following semiconductor materials contains excess free electrons?
The correct answer is A: N-type. Which of the following semiconductor materials contains excess free electrons is N-type. N-type semiconductors have excess electrons (negative charge carriers). For amateur radio operators, this is important for semiconductor knowledge. Understanding this helps when working with semiconductors.
Exam Tip
Semiconductor with excess free electrons = N-type. Think 'N'-type = 'N'egative charge carriers (electrons). N-type semiconductors have excess electrons. Not P-type (holes), not bipolar (transistor), not insulated gate (FET) - just N-type.
Memory Aid
"Semiconductor with excess free electrons = N-type. Think 'N'-type = 'E'lectrons. N-type semiconductors have excess electrons. Important for semiconductor knowledge."
Real-World Application
Semiconductor materials: N-type contains excess free electrons. N-type semiconductors are doped with donor impurities that provide extra electrons. This is the material - N-type has excess free electrons.
Key Concepts
Why Other Options Are Wrong
Option B (P-type): Incorrect. P-type has excess holes, not electrons - N-type has excess electrons. P-type is wrong.
Option C (Bipolar): Incorrect. Bipolar refers to transistor type, not material - N-type has excess electrons. Bipolar isn't the material.
Option D (Insulated gate): Incorrect. Insulated gate refers to FET type, not material - N-type has excess electrons. Insulated gate isn't the material.
题目解析
The correct answer is A: N-type. Which of the following semiconductor materials contains excess free electrons is N-type. N-type semiconductors have excess electrons (negative charge carriers). For amateur radio operators, this is important for semiconductor knowledge. Understanding this helps when working with semiconductors.
考试技巧
Semiconductor with excess free electrons = N-type. Think 'N'-type = 'N'egative charge carriers (electrons). N-type semiconductors have excess electrons. Not P-type (holes), not bipolar (transistor), not insulated gate (FET) - just N-type.
记忆口诀
Semiconductor with excess free electrons = N-type. Think 'N'-type = 'E'lectrons. N-type semiconductors have excess electrons. Important for semiconductor knowledge.
实际应用示例
Semiconductor materials: N-type contains excess free electrons. N-type semiconductors are doped with donor impurities that provide extra electrons. This is the material - N-type has excess free electrons.
错误选项分析
Option B (P-type): Incorrect. P-type has excess holes, not electrons - N-type has excess electrons. P-type is wrong. Option C (Bipolar): Incorrect. Bipolar refers to transistor type, not material - N-type has excess electrons. Bipolar isn't the material. Option D (Insulated gate): Incorrect. Insulated gate refers to FET type, not material - N-type has excess electrons. Insulated gate isn't the material.
知识点
Semiconductor materials, Contains excess free electrons, N-type, Semiconductors
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.