MANUFACTURE OF CIRCUIT SUBSTRATE HAVING THIN CAPACITOR THEREON

摘要

PROBLEM TO BE SOLVED: To provide a circuit substrate with a thin capacitor which allows formation of a ferroelectric film, even on various types of insulating substrates having a low alkali resistance. SOLUTION: A circuit 3 with an adhesive layer made of a multilayer of a bonding synthetic resin sheet 3a and a circuit pattern 3b having a predetermined pattern shape is prepared with use of a copper foil with an adhesive layer. A conductive film 7 containing titanium as its main component is formed on a lower electrode 3c included in the circuit pattern 3b. The circuit 3 with the adhesive layer having the conductive film 7 formed thereon is dipped into a strong alkali solution to form a crystalline ferroelectric film 9 on the conductive film 7 by a hydrothermal synthesis method. An upper electrode 13 is formed on the ferroelectric film 9 to prepare a laminate 1 having a capacitor. Thereafter the bonding synthetic resin sheet 3a of the laminate 1 is bonded onto an insulating substrate 17 which has a low alkali resistance.