A universal integrated wireless digital dental x-ray sensor and positioning apparatus includes a digital array sensor, such as CCD or CMOS, attached to a distal end of a bite block portion through a hinge assembly. Therefore, the automatic hair washer can wash the back of the neck of the person sufficiently, without putting a big burden on the neck. An oxidation barrier layer is formed over a surface of the silicon region adjacent the trench and along the trench sidewalls and bottom. and 65-85%, the emulsifier is 0.