Physical Design for 3D Integrated Circuits

3	Detailed Electrical and Reliability Study of Tapered TSVs Tiantao Lu and Ankur Srivastava

CONTENTS

Abstract

3.1    Introduction

3.2    Tapered TSVs: An Inevitable Byproduct of Manufacturing

3.2.1    TSV Fabrication

3.2.2    Source of Tapering Effect

3.2.3    TSV Tapering in Real Fabrication

3.3    BI-Directional Delays of Tapered TSV

3.4    DC Current Density and Thermal Simulation for Tapered TSV

3.5    Thermal Mechanical Stress Simulation for Tapered TSV

3.5.1    Physical Dimensions and Simulation Setup

3.5.2    Impact of TSV Tapering on KOZ

3.6    Electromigration Simulation for Tapered TSV

3.6.1    Equations for TSV Electromigration

3.6.2    Electromigration Simulation Results for Tapered TSV

3.7    Implications of TSV Tapering on ...