A method of impurity doping into a semiconductor, which comprises irradiating energy rays such as excimer laser beam (or UV-rays) to a predetermined region of a hydrogen terminated silicon surface to remove hydrogen atom layers terminating the silicon surface thereby forming a patterned silicon surface region not terminated with hydrogen and selectively adsorbing impurities on the silicon surface region not terminated with hydrogen, to conduct impurity doping. When such an impurity doping method is adopted, junctions having shallow and abrupt distribution for use in a miniaturized MOSFET or the like can be attained with a lesser number of the steps. Since the impurity doping process can be constituted as a clean and all dry in-situ process without using photoresist at all, it can also provide advantageous effect in view of enhanced yield and shortened production period.