The present invention provides methods for fabricating semiconductor structures and devices, particularly ultra-shallow doped semiconductor structures exhibiting low electrical resistance. The zero frequency controls a frequency range of the signal amplified in the link based on the gain set by the first transconductance circuit. The first switch 1 connects the first terminal a and the second terminal b according to a control signal. These light sources are surface light emitters made by forming a light-emitting layer on a transparent substrate. More particularly, a high activity ZSM-48 with defined purity is prepared, the ZSM-48 being free of non-ZSM-48 seed crystals and ZSM-50.