Abstract: Provided is a semiconductor device, comprising: a semiconductor substrate having an upper surface, a lower surface, and a center position equidistant from the upper surface and the lower surface in a depth direction of the semiconductor substrate. An N-type region with an N-type conductivity is provided in the semiconductor substrate such that the N-type region includes the center position of the semiconductor substrate. The N-type region includes an acceptor with a concentration that is a lower concentration than a carrier concentration, and is 0.001 times or more of a carrier concentration at the center position of the semiconductor substrate.

Abstract: A method of applying to surfaces of component parts of an evaporator hydrophilic coatings which do not emit offensive odors under operating conditions, or at other times. The method provides coatings in which water glass and colloidal silica are attached to the surfaces in the form of solids in an amount of 0.010 to 0.066 g/m.sup.2.

Abstract: A heater (19) is disposed in an air flow duct (12) having an upper air outlet (22). An air filter (36) is disposed in a bypass duct (31) having an outlet (32) communicating with the upper outlet (22). Cool air flows into the bypass duct (31) from the air flow duct (12) upstream of the heater (19). Warm air is mixed with the cold air in the bypass duct (31) and is obtained either from the air flow duct (12) downstream of the heater (19) or is constituted by recirculated air from a vehicle passenger compartment.