A C-Tesla Protocol for Sensor Networks

The present invention is to manufacture a low hydrogen-concentration silicon crystal having less micro defects caused from oxygen precipitation generated during an annealing process. Particularly, a silicon crystal including hydrogen concentration lower than 0.55x1011 cm-3, where the hydrogen concentration dependency is small and the micro defect density is less, may be used for a substrate of semiconductor devices. The low hydrogen-concentration silicon substrate is manufactured by measuring the hydrogen concentrations in a silicon crystal and in a hydrogen-doped silicon crystal having a known hydrogen concentration, where both the silicon crystals have been annealed at an equal condition so as to generate thermal donors therein, and by comparing thus measured hydrogen concentrations. The known hydrogen-doped silicon crystal has been prepared by a hydrogen-diffusing annealing in a hydrogen containing atmosphere, where the hydrogen concentration is calculated from the hydrogen partial pressure and the temperature of the annealing.