TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The compound containing donor element contains phosphorus and/or antimony, and is form of glass particles containing material chosen from phosphorus trioxide, phosphorus pentoxide and antimony trioxide, and glass component substance chosen from silica, potassium oxide, sodium oxide, lithium oxide, barium oxide, strontium oxide, calcium oxide, magnesium oxide, beryllium oxide, zinc oxide, lead oxide, cadmium oxide, vanadium oxide, tin oxide, zirconium dioxide, molybdenum oxide, germanium dioxide, yttria, cerium oxide and titanium dioxide. The compound containing acceptor element contains boron and/or aluminum, and is form of glass particles containing material chosen from boron trioxide and alumina, and glass component substance chosen from silica, potassium oxide, sodium oxide, lithium oxide, barium oxide, strontium oxide, calcium oxide, magnesium oxide, beryllium oxide, zinc oxide, lead oxide, cadmium oxide, vanadium oxide, tin oxide, zirconium dioxide, molybdenum oxide, germanium dioxide, yttria, cerium oxide, titanium dioxide, tungsten trioxide, tellurium dioxide, lanthanum oxide, niobium pentoxide, tantalum pentoxide, lutetium trioxide and manganese oxide, or boron nitride. The content of compound containing donor element or compound containing acceptor element is 0.1-30 %mass. The impurity diffusion layer forming composition further contains 0.01-20 %mass inorganic filler which is fumed silica. The fumed silica is fumed silica by which the surface is hydrophobilized. Preferred Properties: The average particle diameter of glass particles in compound containing donor element or compound containing acceptor element is 0.01-100 mu m.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Properties: The number average molecular weight of the compound (I) is 1000-5 million. The impurity diffusion layer forming composition has TI value of 0.5-2, calculated by log10(( eta )0.01)-log10(( eta )10), where (eta)0.01 is shear viscosity at 25 degrees C and shear rate of 0.01 s-1, and ( eta )10 is shear viscosity at shear rate of 10 s-1. Preferred Composition: The dispersion medium contains terpineol, dihydroterpineol, diethylene glycol monobutyl ether and/or acetic acid diethylene glycol butyl ether. The impurity diffusion layer forming composition further contains cellulose derivative, acrylic resin and/or alkyd resin, and alkoxysilane. The content of compound (I) is 0.1-30 %mass.