native channel和implant adjust channel的区别

弱问，看见文章里说，native channel的device的噪声性能优于implant adjust channel的，不知道这两分别指的是什么沟道类型，为什么native的要好一些呢，期待大侠解惑~

Native channel refers to MOSFETs built with intrisic threshold without threshold adjustment step. MOSFET intricsic threshold depends on the the flatband voltage of the MOS capacitor and the difference of the work functions of the gate/substrate material. For example, the intrisic threshold for an poly-gate NMOS could be as low as zero or tens of millivolts. To make a practical MOSFET, additional step (typically done by Ion implantation) is needed to bring this threshold to around, for example, 600mV. Ion implantation is a brutal process which damages the crystal structure of the channel, even after annealing, there would still some crystal structure defects expected, which will distrub an even current flow, increase the noise of the device.