. . . . "Examplesthereof are as follows:(where, p, r, s, t, u, v, w and X are the same as above.)Instead of the above-mentioned bonding materials, the bonding material compounds specifically listed below can be used.Furthermore, as the chemically bonding material, in general, a substance expressed by a formula SiX.sub.k (OA).sub.4-k (X is the same as above, A is an alkyl group, and k is 0, 1, 2, or 3) can" . .