Symmetrical / asymmetrical bidirectional S-shaped I-V characteristics with trigger voltages
ranging from 10 V to over 40 V and relatively high
holding current are obtained for advanced sub-micron silicided
CMOS (Complementary
Metal Oxide Semiconductor) /
BiCMOS (Bipolar
CMOS) technologies by custom implementation of P1-N2-P2-N1 / / N1-P3-N3-P1 lateral structures with embedded
ballast resistance 58, 58A, 56, 56A and periphery guard-ring isolation 88-86. The bidirectional protection devices render a high level of
electrostatic discharge (ESD)
immunity for advanced
CMOS /
BiCMOS processes with no latchup problems. Novel design-adapted multifinger 354 / interdigitated 336
layout schemes of the ESD protection cells allow for scaling-up the ESD performance of the protection structure and custom integration, while the I-V characteristics 480 are adjustable to the operating conditions of the
integrated circuit (IC). The ESD protection cells are tested using the TLP (
Transmission Line Pulse) technique, and ESD standards including HBM (
Human Body Model), MM (
Machine Model), and IEC (International Electrotechnical Commission) IEC 1000-4-2 standard for ESD
immunity. ESD protection performance is demonstrated also at high temperature (140° C.). The unique
high ratio of dual-polarity ESD protection level per unit area, allows for integration of fast-response and compact protection cells optimized for the current tendency of the
semiconductor industry toward low cost and
high density-oriented IC design. Symmetric / asymmetric dual polarity ESD protection performance is demonstrated for over 15 kV HBM, 2 kV MM, and 16.5 kV IEC for sub-micron technology.