the first step of forming, on {HEAD ~ a joining surface} of a base body of a metal oxide, a solution layer formed of a solution in which a first compound containing aluminum and oxygen and a second compound containing {TAIL ~ boron} and oxide dissolve, 
the first step of forming , on { HEAD ~ a joining surface } of a base body of a metal oxide , a solution layer formed of a solution in which a first compound containing aluminum and oxygen and a second compound containing { TAIL ~ boron } and oxide dissolve ,
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH