A method including providing a silicon-on-insulator (SOI) substrate including a SOI layer, a buried oxide layer, and a base layer; the buried oxide layer is located below the SOI layer and above the base layer, and the buried oxide layer insulates the SOI layer from the base layer; etching a deep trench into the SOI substrate, the deep trench having a sidewall and a bottom, the deep trench extends from a top surface of the SOI layer, through the buried oxide layer, down to a location within the base layer; forming a dielectric liner on the sidewall and the bottom of the deep trench; forming a conductive fill material on top of the dielectric liner and substantially filling the deep trench, the fill material being thermally conductive; and transferring heat from the SOI layer to the base layer via the fill material.