Inter-strata Connection Characteristics and Signal Transmission in Three-dimensional (3D) Integration Technology

Syed Alam,  Robert Jones,  Shahid Rauf,  Ritwik Chatterjee
Freescale Semiconductor


Abstract

In a general case of three-dimensional (3D) Integrated Circuit (IC) technology, it is desirable to design a die for 3D integration with flexibility to facilitate integration with a number of other circuit dies. We present a generic circuit technique which minimizes power consumption and circuit area while allowing reliable signal transfer between 3D dies as well as enabling the design of a bonded interface circuitry without a complete knowledge of inter-strata connection configurations. We also present parasitic RC characteristics of inter-strata connection elements, such as micro-bumps and through-substrate vias, and discuss the technology scaling trends. An inter-strata signal transmission, according to our method, has receive and transmit circuitry with programmable power supply which can be independently controlled for achieving optimum power and signal drive. In addition, the receive circuitry includes hysteresis to allow superior signal integrity in the presence of inter-strata parasitic variations.