NOVELTY - A power semiconductor module (11) has a carbon fiber-metal composite (5) made of carbon fiber and copper or copper alloy and provided between the silicon nitride insulated substrate (7) and metal circuit board (2); a heat dissipating plate (8) made of copper or copper alloy. The thermal conductivity of carbon fiber-metal composite in a direction in which carbon fiber of carbon fiber-metal composite is oriented is set to 400 watts per meter Kelvin or more. Carbon fiber-metal composite and metal circuit is mutually brazed with silver-copper-indium filler metallic brazing material.    USE - Power semiconductor module for vehicle-mounted inverter (claimed) disposed in vehicle-mounted electric system as controller for controlling driving of vehicle-mounted motor of hybrid electric vehicle. Can also be used in inverter mounted in industrial electric system such as motor driving system in factory or inverter mounted in home electric system such as home photovoltaic power generation system or home motor driving system.    ADVANTAGE - Increases cooling performance by reducing thermal resistance between the semiconductor chip and heat dissipating mechanism if carbon fiber-metal composite in which carbon is oriented in one direction is disposed in the thickness direction. Reduces size and cost and increases reliability of the electric power converting system and vehicle-mounted electric system by using the power semiconductor module. Provides power module with low thermal resistance and requires less mounting space due to use of less semiconductor chips, thus provides smaller inverter, thereby compact, highly reliable motor driving system mounted on hybrid electric vehicle is provided at low cost.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method of manufacturing a power semiconductor module.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross sectional view of the structure of a power semiconductor module.    Metal circuit board (2)    Carbon fiber-metal composite (5)    Silicon nitride insulated substrate (7)    Heat dissipating plate (8)    Power semiconductor module (11)