I have one more question which is bothering me! In an instrinsic semiconductor, ni = pi and NiPi = Ni^{2} which is fine, makes sence and all but what i dont really understand is for an extrinsic semiconductor, this rule still applies, say for example you wanted to find the amound of minority carriers in an N type semiconductor which would obviously be holes, the formula says that the Na (number of holes) = Ni squared / Nd (number of donors)
What i am saying is why is it that the number of holes multiplied by the number of electrons is equal to the number of holes multiplied by the number of electrons in an intrinsic semiconductor? I mean why couldnt i just as easily say the number of holes PLUS the numer of electrons in an extrinsic semiconductor = to the number of holes PLUS the number of electrons in an intrinsic semiconductor.
I have already asked this question to my lecturer and I didnt realy understand anything he said about it. He seems to think that this should be obvious but i am sorry i am just not seeing it.
What i am saying is why is it that the number of holes multiplied by the number of electrons is equal to the number of holes multiplied by the number of electrons in an intrinsic semiconductor? I mean why couldnt i just as easily say the number of holes PLUS the numer of electrons in an extrinsic semiconductor = to the number of holes PLUS the number of electrons in an intrinsic semiconductor.
I have already asked this question to my lecturer and I didnt realy understand anything he said about it. He seems to think that this should be obvious but i am sorry i am just not seeing it.