So in a wafer, in the process of dopant addtion and diffustion, I understand it is ion implantation to blow a a donor to the vacant space. Does this apply only to P? how about N type? In reality, for a transistor, do PNP sit above each other? or in the same planor?
If one sits above another, that means, when blowing ion, there has to be some kind of strength difference?
Either or both. In some transistor designs, the layers are horizontal. In others, they're vertical / side-by-side. In many, there's a combination of these two techniques.
As an example - many power MOSFET designs these days are vertical (VMOSFET) or trench. High power density, low on-resistance and thus low losses, and thus preferred for high-power switching (motor drive, switch-mode power supplies, etc.). However, there's still a market for the older 'lateral' MOSFETs, which seem to find favor in linear amplification applications such as audio-frequency power amps.
Yup. If the ions are implanted via a beam, the energy of the beam (i.e. the momentum of the ions) controls how deeply they penetrate the base material before coming to rest.
Ion-beam methods aren't the only ones used for doping. Thermal diffusion of a gas-transported dopant is another.
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