A NOVEL PLANARIZATION TECHNIQUE FOR A HIGH-T-C MULTILEVEL IC PROCESS

A novel technique has been developed to planarize insulating layers wh ich may be used in a YBa2Cu3O7-delta (YBCO) IC process, The technique, called complementary mask planarization (CoMP), has been successfully implemented to planarize line gratings etched in an SrTiO3 insulator. The average surface roughness of the line gratings as measured by an atomic force microscope (AFM) was reduced from 3000 to 250 Angstrom af ter planarization, Films of YBCO were deposited and patterned in the f orm of narrow strips over the line gratings to simulate insulated cros sovers in IC structures, The I-V characteristics of the YBCO strips ov er planarized line gratings showed that the critical current density i s higher by two orders of magnitude than those over unplanarized grati ngs.