Use of vortex generators to improve efficacy of heat sinks used to cool telecommunications, electrical and electro-optical components. According to the present invention, the electromagnetic shielding sheet can endure metal working processes and has high electromagnetic wave shielding properties, resulting in a thin, very flexible fabric sheet. A conductive layer is then deposited onto the first surface of the barrier layer. The hydrogen atoms thus dissociated are released from the compound semiconductor, to thereby activate the p-type impurity. The subset of pixels can be selected to not include pixels on the boundary of the block of pixels. The abraded casting surface is cooled to a temperature in the range of about 100\xb0 to 210\xb0 F.