Method for surface passivation and protection of cadmium zinc telluride crystals

A method for reducing the leakage current in CZT crystals, particularly Cd1-xZnxTe crystals (where x is greater than equal to zero and less than or equal to 0.5), and preferably Cd0.9Zn0.1Te crystals, thereby enhancing the ability of these crystal to spectrally resolve radiological emissions from a wide variety of radionuclides. Two processes are disclosed. The first method provides for depositing, via reactive sputtering, a silicon nitride hard-coat overlayer which provides significant reduction in surface leakage currents. The second method enhances the passivation by oxidizing the CZT surface with an oxygen plasma prior to silicon nitride deposition without breaking the vacuum state