Semiconductor heat sink dipped in coolant - has roughened surface assisting boiling coolant bubble formation and flow

摘要

The heat sink, together with the power semiconductor, is immersed in a non-conductive, low boiling point liquid coolant. It has a rough surface, obtained by sand blasting, knurling, casting etc., in order to enhance the formation of gas bubbles when the coolant is brought to boiling. The heat sink may have a cylindrical or cubical shape with a given number of vertical bores also enhancing the flow of both bubbles and coolant. Two heat sinks discs may be conected by brazed pins, or a one piece casting of identical geometry may be used. The heat sink is suitable to reduce power losses with resulting incrase of service life.