Zhen Peng

Full-Wave Real-Life 3-D Package Signal Integrity Analysis Using Nonconformal Domain Decomposition Method

Advances in interconnect technologies, such as the increase of the number of metal layers and 3-D stacking technique, have paved the way for higher functionality and superior performance while reducing size, power, and cost in todays integrated circuit and package products. However, whether or not the package preserves signal integrity (SI) has become a crucial concern for system designers. In this study, a systematic full-wave numerical approach, based on a nonconformal finite-element domain decomposition method (DDM), is proposed for 3-D real-life circuit/package simulations. First, an automatic domain partitioning strategy is utilized to divide the entire model into a number of sub-domains. Each sub-domain is then meshed independently and an h-version of adaptive mesh refinement is employed. Next, a nonoverlapping DDM is adopted to efficiently solve the finite-element matrix equation. Afterwards, a model-order reduction technique is exploited to compute the multiport spectral responses. SI effects such as signal delay, coupling, and reflection are simulated on a product-level package benchmark. Finally, numerical results verify the analysis and demonstrate the effectiveness of the proposed method.

Signal Integrity Analysis of High-Speed Interconnects by Using Nonconformal Domain Decomposition Method

3-D interconnect techniques in multilayer very large scale integration design, such as stacked layers and various chip-stacking systems, have paved the way for the improvement of integrated circuit density and operation speed. However, these techniques often accompany with impedance discontinuities that induce signal integrity (SI)/power integrity and electromagnetic interference effects. Consequently, SI analysis serves as one of the key guidelines of chip-package-board design in deep submicrometer technology. However, full-wave numerical analysis of 3-D high-speed and high-density interconnects is also considered to be a great challenge. In this paper, a nonconformal domain decomposition method with second-order transmission condition for SI analysis of high-speed interconnects on a multiscale multilayer printed circuit board is presented. The accuracy and robustness of the proposed method are first witnessed by modeling a six-layer two-trace differential pair. Then we study a 14-layer 16-trace interconnect model to demonstrate the efficiency of the method. Eye diagrams of the two models are also presented in the time-domain SI analysis.

Thermal Analysis of High-Power Integrated Circuits and Packages Using Nonconformal Domain Decomposition Method

A nonconformal domain decomposition method (DDM) is proposed to solve moderately stiff parabolic partial differential equations in inhomogeneous domains. The proposed nonconformal DDM decomposes the entire problem domain into many nonoverlapping subdomains. Consequently, it is effective in addressing complex thermal problems of electronic systems with multiscaled features. Moreover, the time discretization employed is based on an unconditionally stable and implicit Euler scheme. The unconditionally stable time-marching algorithm is beneficial since the time-step size is no longer governed by the spatial discretization of the mesh, but rather by the desired accuracy. Additionally, this paper includes numerical investigations of the convergence properties of the proposed nonconformal DDM. Finally, numerical results are shown for a chip-package-printed circuit board example with thermal cooling by both natural convection and forced convection of heat sinks.

Analysis of IR-drop in 3-D IC packaging using a non-conformal domain decomposition method

In this paper, we present a non-conformal, non-overlapping domain decomposition method (DDM) for the IR drop analysis of high-power integrated circuit (IC) package in which both dielectrics and non-ideal conductors coexist. The proposed non-conformal DDM starts by partitioning the composite device into inhomogeneous sub-regions. Subsequently, each sub-domain is meshed independently according to its own characteristic features. As a consequence, the troublesome mesh generation task for complex ICs can be greatly relaxed. The proposed non-conformal DDM has been applied to analyze the IR drops in the power delivery networks (PDNs) of complex ICs. Numerical results of a product-level IC package demonstrate the flexibility and potentials of the non-conformal DDM.

High speed interconnects of multi-layer PCB analysis by using non-conformal domain decomposition method

A non-conformal domain decomposition method (DDM) is proposed to investigate signal integrity (SI) of high-speed interconnects on multi-scale, multi-layer printed circuit board (PCB) in this paper. The accuracy and robustness of the proposed method is first demonstrated by analysis of a 4-layer differential pair. Then we studied a 14-layer 16 traces interconnect model to demonstrate the efficiency of the method. Eye diagrams of the two models are studied for time domain SI.

SI and PI analyses of complex IC packagings using non-conformal domain decomposition methods

In this paper, we present non-conformal, non-overlapping domain decomposition methods (DDMs) for DC IR drop and AC signal integrity (SI) analyses of high-power chip-package-PCBs. The proposed non-conformal DDMs start by partitioning the composite device into inhomogeneous sub-regions with temperature-dependent material properties. Subsequently, each sub-domain is meshed independently according to its own characteristic features. As a consequence, the troublesome mesh-generation task for complex ICs can be greatly relaxed. Numerical example of SI/PI analyses of a complex IC package demonstrates the flexibility and potentials of the proposed non-conformal DDMs.

Electromagnetics-thermal co-analysis of real-life 3-D ICs using non-conformal domain decomposition method

Advances in integrated circuit (IC) and package technologies, such as the increase of the number of metal layers and 3-D stacking technique, have paved the way for faster speed and higher performance in todays electronic products. However, continuing down-scaling in feature size poses crucial issues, such as the parasitic couplings between circuit elements and localized Joule heat dissipation. In this work, we introduce a systematic computational Electromagnetic (CEM)-thermal coupling approach capable of dealing with multiscale problems such as 3-D ICs and subsystems. A non-conformal finite element domain decomposition method is utilized to iterative the electrostatic, full-wave electromagnetic and thermal simulation. Moreover, we included preliminary numerical results demonstrating the effectiveness of the proposed approach.

3-D full-package signal integrity analysis using domain decomposition method

Advances in integrated circuit and package technologies, such as the increase of the number of metal layers and 3-D stacking technique, have paved the way for faster speed and higher performance in todays electronic products. However, whether the high-speed systems preserve signal integrity has become a crucial question for system designers. In this work, we introduce a systematic numerical simulation method for 3-D full package simulation. A non-conformal finite element domain decomposition method with second order transmission condition is proposed to iterative the matrix equation solution. Numerical results verify the analysis and demonstrate the effectiveness of the proposed method on a real-life 3-D full package signal integrity analysis.

Co-simulations of electromagnetic and thermal effects in electronic circuits using non-conformal numerical methods

Advances in interconnect technologies, such as the increase of the number of metal layers and 3-D stacking technique, have paved the way for higher functionality and superior performance while reducing size, power, and cost in todays integrated circuits and package products. With the increase of clock frequency and edge rates as well as the continuously downscaling of feature size and 3-D interconnect technologies in high-speed systems, signal integrity (SI) effects such as signal delay, reflection, attenuation, dispersion and crosstalk have become one of the dominant factors in current deep sub-micrometer CMOS technologies limiting overall performance of high-speed systems.

Plane wave scattering from a partially coated air platform using a non-overlapping surface integral equation domain decomposition method

We address in detail the numerical simulations of electromagnetic (EM) wave scattering from a mockup partly coated fighter jet in this presentation. The majority part of the fighter jet surface is considered to be perfect electric conductor (PEC). The horizontal stabilizer, vertical stabilizer and the wings are coated with high-density materials, whereas a hollow dielectric radome is located at the front of the aircraft. Due to the nature of unbounded problem domain, and the desire to avoid a three dimensional discretization, we attempt to compute the numerical approximation using the boundary integral equations (BIEs), or the method of moments (MoM). However, it turns out not to be an easy quest. In the presentation, we shall elucidate difficulties that we have encountered and innovative techniques that we have devised during our journey to solve such a challenging mutli-scale EM application.