Abstract: With a view to preventing increases in forward voltage due to a change with the lapse of time of a bipolar semiconductor device using a silicon carbide semiconductor, a buffer layer, a drift layer and other p-type and n-type semiconductor layers are formed on a growth surface, which is given by a surface of a crystal of a silicon carbide semiconductor having an off-angle ? of 8 degrees from a (000-1) carbon surface of the crystal, at a film growth rate having a film-thickness increasing rate per hour h of 10 ?m/h, which is three times or more higher than conventional counterparts. The flow rate of silane and propane material gases and dopant gases is largely increased to enhance the film growth rate.

Abstract: A lubricated bearing apparatus for a hydraulic machinery has rotary-side ceramic sliding plates disposed in contact with bearing-side ceramic sliding plates. The rotary-side ceramic sliding plates are disposed in receiving grooves of a main shaft sleeve member fixed to the main shaft. The main shaft sleeve member is provided with preventing portions for preventing the rotary-side ceramics sliding plates from being broken by the centrifugal force. Thus, ceramic materials can be used both on the rotary side and the bearing side, thereby lengthening the usable life of the bearing apparatus.