導dao體ti三san極ji管guan中zhong參can與yu導dao電dian的de有you兩liang種zhong極ji性xing的de載zai流liu子zi，所suo以yi也ye稱cheng為wei雙shuang極ji型xing三san極ji管guan。本ben文wen介jie紹shao另ling一yi種zhong三san極ji管guan
，這zhe種zhong三san極ji管guan隻zhi有you一yi種zhong載zai流liu子zi參can與yu導dao電dian，所suo以yi也ye稱cheng為wei單dan極ji型xing三san極ji管guan，因yin為wei這zhe種zhong管guan子zi是shi利li用yong電dian場chang效xiao應ying控kong製zhi電dian流liu的de，所suo以yi也ye叫jiao場chang效xiao應ying三san極ji管guan(FET)，簡稱場效應管。MOS在電路中應用很常見，主要作為開關管，在電機驅動電路中常見。