NOVELTY - A localized heating reducing-device has an electrode for applying an electrical bias across the optical waveguide, and a contact layer for providing an interface between the electrode and optical wavelength. The contact layer has an electrically and thermally conductive first region, and a thermally and non-electrically conductive second region for dissipating heat in a localized heating region.    USE - For reducing localized heating in an optical waveguide (102) useful in an electro-absorption modulator, a Mach-Zehnder modulator, a laser, a photo-detector, or a semiconductor optical amplifier (claimed).    ADVANTAGE - The invention prevents overheating in a region near the point of optical entry and prevents undesirable electrical contact between electrode and the region. It permits greater optical power to be delivered to the device. A higher reverse bias voltage can be used to modulate the light signal, thus permitting increased speed of the device.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) A method for reducing localized heating in a device for controlling the passing light; and    (2) A method of manufacturing the inventive device comprising adding a contact layer of electrically conducting and thermally conducting material to a surface of a waveguide, masking the contact layer, etching away the electrically conducting material in an exposed region of the contact layer, adding a blanket deposit of an electrically insulating and thermally conducting material to the first region and the etched away second region of the contact layer, masking the second region and leaving exposed at least a part of the first region, etching the electrically insulating and thermally conducting material in the exposed part of the first region, and depositing metal into the contact layer to form the electrode.    DESCRIPTION OF DRAWING(S) - The figure shows a section view of an optical modulator.    Optical waveguide (102)    Contact layer (110)    Electrode (112)