Electrical and noise properties of vacuum deposited thin germanium films

The excess noise generated in germanium film and the contact noise generated in the contacts between the metal and the Ge film, as well as the electrical properties of Ge film were investigated. Measurements of the Hall effect parameters, and the resistivity of the Ge films indicate that a film deposited at a higher substrate temperature has a lower majority carrier concentration and resistivity, but higher Hall coefficient and mobility. The excess noise generated in Ge films was found to decrease as the deposition substrate temperature was increased. A technique is described for measuring the contact noise voltage.