[问答题] 什么是N型半导体？P型半导体？

G-6-PD患者应避免食用（） ["酵母","绿叶蔬菜","蚕豆","黄豆","蛋黄"] 锅炉热工信号系统和电气信号系统的作用？ 被称为治疗缺铁性贫血的特效药是（） ["维生素C","维生素B₁₂","铁剂","叶酸","维生素A"] 病毒性心肌炎恢复期应限制活动至少（） ["2个月","3个月","4个月","5个月","6个月"] 病毒性心肌炎有心脏扩大的患儿，需卧床休息（） ["2个月","3个月","4个月","5个月","6个月"] 什么是N型半导体？P型半导体？