A cooling device is provided for liquid cooling a power semiconductor device. The device includes a coolant diverter for guiding liquid coolant to the power semiconductor device. The coolant diverter has a first plate for dividing the coolant diverter into a first cavity and a second cavity. The second cavity positioned adjacent the power semiconductor device. The first plate further includes an opening to fluidly couple the first cavity with the second cavity such that the liquid coolant flows into the first cavity, through the opening in the first plate, and into the second cavity to cool the power semiconductor device. The first cavity has a cross-sectional area that generally decreases in a downstream direction, and the second cavity has a cross-sectional area that generally increases in the downstream direction.