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Wafer-To-Wafer Permanent Bonding REVERSE COSTING® – STRUCTURAL, PROCESS & COST REPORT Wafer Bonding Comparison Permanent Bonding – Physical analysis and Cost Overview MEMS, Imaging, LED, Packaging report by Audrey LAHRACH November 2018 – Sample 22 bd Benoni Goullin 44200 NANTES - FRANCE +33 2 40 18 09 16 [email protected] www.systemplus.fr ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 1 Table of Contents Overview / Introduction 5 o Thermo-compression Bonding o Executive Summary o MEMS RF o Reverse Costing Methodology o MEMS Inertial Sensor Permanent Wafer Bonding Technology 9 Physical Comparison 140 Permanent Wafer Bonding Definition and Process Description 13 o Without intermediate layer Cost Comparison 164 o Fusion Bonding o CMOS Image Sensor Feedbacks 168 o MEMS Inertial Sensor SystemPlus Consulting services 170 o Cu-Cu/Oxide Hybrid Bonding o CMOS Image Sensor o Anodic Bonding o MEMS Pressure Sensor o With intermediate layer o Glass Frit o MEMS Pressure Sensor o MEMS Inertial Sensor o Adhesive Bonding o MEMS Micro-mirror o Eutectic Bonding o MEMS Inertial Sensor o Microbolometer o LED ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 2 Executive Summary Overview / Introduction o Executive Summary This comparative review has been conducted to provide insights into the structures, processes and costs of the main o Reverse Costing Methodology permanent wafer bonding technologies. o Glossary Wafer Bonding Technology Among these technologies, we have identified two main groups. One, bonding wafers without intermediate layers, includes Wafer Bonding Definition and fusion, copper-copper hybrid and anodic bonding approaches. The second group involves bonding wafers with intermediate Process Description layers using an insulator like a glass frit, or a metal in eutectic and thermocompression approaches. In this report, we show examples of each wafer bonding approach in different applications. We analyze and compare each wafer bonding process type Physical Comparison to show the benefit in terms of cost and space used. Cost Comparison Related Reports By switching from glass frit bonding to metal bonding thermo-compression, a manufacturer could reduce component area by up to 30%, reclaiming lost space around the active surface and cutting cost. However, some bonding technologies are currently About System Plus used only in some market segments. For example, hybrid copper-copper bonding is only used in CIS and glass frit technology is found only in products in automotive and some consumer MEMS applications. In the comparison, we have analyzed each component’s wafer bonding process, including component dimensions, cost and manufacturing approach. We provide an overview of technology costs and manufacturer choices by application and range. We offer buyers and device manufacturers a unique possibility of understanding permanent wafer bonding technology, evolution, and comparing process costs. ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 3 Wafer Bonding Overview / Introduction Permanent Wafer Bonding: Wafer Bonding Technology . Wafer bonding consists of joining two wafers surfaces with or without an intermediary layer, depending on the bonding Wafer Bonding Definition and technology. Process Description Direct bonding is the process of bonding without an intermediate layer: Physical Comparison Cost Comparison Related Reports About System Plus Indirect bonding is the process of bonding with an intermediate layer: ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 4 Technology Description Overview / Introduction Fusion Wafer Bonding Technology bonding/direct or Wafer Bonding Definition and molecular bonding Process Description Direct Bonding Physical Comparison Cu-Cu/oxide hybrid Without bonding at RT intermediate layer Cost Comparison Related Reports Anodic bonding About System Plus Wafer Bonding Technologies Glass frit bonding Insulating interlayer Adhesive bonding Indirect Bonding With intermediate layer Eutectic Bonding Metal bonding Thermo- compression Permanent bonding Technologies Overview ©2018 by System Plus Consulting ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 5 Fusion Bonding Overview / Introduction Wafer Bonding Technology Wafer Bonding Definition and Process Description o Without intermediate layer o Fusion bonding o Anodic bonding o With intermediate layer o Insulating interlayer o Glass frit bonding o Adhesive bonding o Metal Bonding o Cu-Cu/oxide hybrid bonding o Eutectic Bonding o Thermo- compression Physical Comparison Cost Comparison Related Reports About System Plus ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 6 mCube Accelerometer - Package Cross-Section Overview / Introduction ASIC Wafer Bonding Technology Wafer Bonding Definition and Fusion Process Description bonding o Without intermediate layer o Fusion bonding Photo MEMS o Anodic bonding rotation Sensor o With intermediate layer (180°) o Insulating interlayer Resin o Glass frit bonding Resin o Adhesive bonding MEMS o Metal Bonding Cap IC Substrate (Si) o Cu-Cu/oxide hybrid TSV via Middle bonding Fusion o Eutectic Bonding Bonding MEMS Cap (Si) o Thermo- xxxx xxxx compression IC Metal Layers MEMS Sensor (Si) xxxx Physical Comparison xxxx xxxx xxxx TSV MEMS Cap (Si) Cost Comparison xxxxx xxxxx Related Reports Solder RDL MEMS Sensor Ball (Si) About System Plus Fusion Bonding Oxide CMOS and Metal Layers Package Cross-Section – SEM View IC Substrate (Si) mCube – Die Cross-Section – SEM View ©2018 by System Plus Consulting ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 7 mCube Accelerometer – Process Flow Overview / Introduction Wafer Bonding Technology • Front-End Process: o Substrate: x-inch (xxxmm) Silicon wafer Wafer Bonding Definition and Process Description o Process type: xxxxxxxx o o Without intermediate layer Metal layers: x (xxxx) o Fusion bonding o Special features: DRIE, fusion & xxxxx bondings + o Anodic bonding o With intermediate layer TSV xxxxxx in MEMS Cap o Insulating interlayer o Glass frit bonding o Lithography steps: xx o Adhesive bonding o MEMS Area: xxxmm² o Metal Bonding o Cu-Cu/oxide hybrid bonding o Eutectic Bonding o Thermo- compression Physical Comparison TSV MEMS Cap Cost Comparison Related Reports MEMS Sensor Fusion About System Plus bonding IC die MEMS Accelerometer structure ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 8 Fusion Bonding – mCube Accelerometer - Process Flow Overview / Introduction Fusion Bonding Process Wafer Bonding Technology Wafer Bonding Definition and Process Description o Without intermediate layer o Fusion bonding o Anodic bonding o With intermediate layer • IC wafer o Insulating interlayer o Glass frit bonding MEMS on o Adhesive bonding o Metal Bonding CMOS o Cu-Cu/oxide hybrid bonding o Eutectic Bonding o Thermo- compression Physical Comparison • Fusion bonding Cost Comparison MEMS on Related Reports CMOS About System Plus ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 9 PHYSICAL COMPARISON ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 10 Glass frit bonding to Thermo-compression bonding Overview / Introduction MEMS Wafer Bonding Technology Cap Wafer Bonding Definition and Process Description Pb Glass-frit Physical Comparison Cost Comparison Related Reports MEMS Sensor About System Plus Glass-Frit Sealing Cross section MEMS xxxµm Accelerometer with Glass-Frit Sealing xxµm ©2018 by System Plus Consulting Opening ©2018 by System Plus Consulting MEMS Cap Gold MEMS Sensor Au-Au Sealing Cross-Section Accelerometer with Gold Sealing ©2018 by System Plus Consulting ©2018 by System Plus Consulting ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 11 Glass frit bonding to Eutectic bonding Overview / Introduction Wafer Bonding Technology MEMS Wafer Bonding Definition and Cap Process Description Pb Glass-frit Physical Comparison Cost Comparison Related Reports About System Plus MEMS xxxxxx Sensor 6-axis eCompass Glass-Frit Sealing Cross section xxxµm ©2018 by System Plus Consulting xxµm MEMS Cap xxxxxx MEMS Sensor WLCSP 3-axis AlGe Accelerometer AlGe Sealing Cross section ©2018 by System Plus Consulting ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 12 COST COMPARISON ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 13 Permanent Wafer Bonding Comparison Overview / Introduction Wafer Bonding Technology Front-End Wafer Bonding Definition and Process Description Clean Room Cost Physical Comparison Equipment Cost Consumable Cost Cost Comparison Labor Cost Related Reports Wafer Bonding Cost About System Plus Xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx Xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx ©2018 by System Plus Consulting | Wafer to Wafer Permanent Bonding Comparison 2018 14 Related Reports Overview / Introduction Wafer Bonding Technology Wafer Bonding Definition and REVERSE COSTING ANALYSES - SYSTEM PLUS CONSULTING MARKETMARKET AND AND TECHNOLOGY TECHNOLOGY REPORTSREPORTS - YOLE DÉVELOPPEMENTDÉVELOPPEMENT Process Description PACKAGING ADVANCED PACKAGING Physical Comparison • MEMS Packaging: Reverse Technology Review • Bonding and Lithography Equipment Market for More than Moore
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