A robust embedded ladder-oxide/Cu multilevel interconnect technology for 0.13 μm complementary metal oxide semiconductor generation

A robust embedded ladder-oxide {k = 2.9)/copper (Cu) multilevel interconnect is demonstrated for 0.13 μm complementary metal oxide semiconductor (CMOS) generation. A stable ladder-oxide intermetal dielectric (IMD) is integrated by the Cu metallization with a minimum wiring pitch of 0.34 μm, and a single damascene (S/D) Cu-plug structure is applied. An 18% reduction in wiring capacitance is obtained compared with that in SiO ₂ IMDs. The superior controllability of metal thickness by the S/D process enables us to enhance the MPU maximum frequency easily. The stress-migration lifetime of vias on wide metals for the S/D Cu-plug structure is longer than that for a dual damascene (D/D) structure. Reliability test results such as electromigration (EM), the temperature dependant dielectric breakdown (TDDB) of Cu interconnects, and pressure cooker test (PCT) results are acceptable. Moreover, a high flexibility in a thermal design is obtained.