We have fabricated direct-injection high-Tcsuperconducting quantum interference devices (SQUIDs) with integrated YBa2Cu3O7−x(YBCO) ground planes in the upper part of structure. The YBCO/PrBa2Cu3O7−x(PBCO)/YBCO edge junctions with 10-nm-thick PBCO barriers showed RSJ-like current-voltage(I–V)characteristics before and after the ground plane formation. We measured the voltage modulations of these SQUIDs with two different hole sizes to evaluate the line inductance. At a temperature of 30 K, the estimated line inductance under the ground plane was about 1.0pH/□, while the estimated line inductance without the ground plane was 2.8pH/□. ©1997 American Institute of Physics.