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© 2010 by SYSTEM PLUS CONSULTING, all rights reserved. AKM AK8973S 2
Table of Contents
Glossary
1. Overview / Introduction……………………….…........…4
– Executive Summary
– Reverse Costing Methodology
2. AKM Company Profile …...……………....……...............6
– AKM Product line
– AK8973S Block Diagram
– AKM Business Model
3. Physical Analysis……………………….………......…...11
– Synthesis of the Physical Analysis
– Physical Analysis Methodology
– Package Characteristics & Markings
– Package X-Ray
– Device Structure
– ASIC – Dimensions
– ASIC – Pads Distribution Reconstitution
– ASIC – Block Functions
– ASIC – Markings
– ASIC – Bond Pads
– ASIC – Capacitors/Resistors
– ASIC – Hall Sensors
– CMOS Hall Sensor Principle
– Component Cross-Sections
– Physical Data Summary
– Process Characteristics
– AKM Electronic Compasses – Dies Comparison
4. Manufacturing Process Flow…………………………..….45
– Overview
– ASIC Process Flow
– Packaging Process Flow
– Description of the Wafer Fabrication Units
5. Cost Analysis……………………………………………..…..52
– Synthesis of the Cost Analysis
– Main Steps of Economic Analysis
– Supply Chain Analysis
– Yields Explanation
– Yields Hypotheses
– Front-End : Hypotheses
– Front-End Cost
– Back-End 0 : Probe Test Cost
– Die per wafer & Probe Test
– Back-End 0 : Packaging Hypotheses
– Back-End 0 : Packaging Cost
– Back-End 0 : Packaging Cost per Process Steps
– Back-End 0 : Dicing Cost
– Total Wafer Cost (Front-End + Back-End 0)
– Back-End 1 : Final Test & Calibration Cost
– AK8973S Cost (FE + BE 0 + BE 1)
6. Estimated Manufacturer Price Analysis ………………...72
– Definitions of Prices
– Manufacturers financial ratios
– Estimated Manufacturer Price
Conclusion ………………………………………………………76
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© 2010 by SYSTEM PLUS CONSULTING, all rights reserved. AKM AK8973S 7
Principle of the Si-monolithic geomagnetic sensor. Left: A cross-sectional view of the focusing of
magnetic field lines into Si monolithic Hall sensors by the magnetic concentrator, length L and thickness
t. Right: A plan of the relative positions of the magnetic concentrator and Si monolithic Hall elements.(Courtesy of Asahi Kasei Microdevices)
CMOS Hall Sensor with IMC Principle
• The AKM electronic compass uses the integrated magnetic concentrator (IMC)
technology to measure and extrapolate magnetic field on 3 axis.
• A circular ferromagnetic concentrator bends magnetic fields into four CMOS Hall
sensors positioned at each 90° angle under the concentrator periphery. These sensors
can measure the magnetic field in the X and Y directions. By adding and subtracting
these measures, the magnetic field in the Z direction can be implemented.
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© 2010 by SYSTEM PLUS CONSULTING, all rights reserved. AKM AK8973S 13
Packaging Cost per Process Steps (2/2)
Packaging Step Cost Breakdown
Repassivation - Cleaning $1,10 0,7%
Repassivation - Measurement $0,66 0,4%
Repassivation - Polyimide Deposition (5.6µm) $7,19 4,7%
Repassivation - Pattern $0,88 0,6%
Repassivation - Cleaning $2,76 1,8%
Repassivation - Measurement $0,66 0,4%
UBM Barrier/Seed - TiN deposition $4,79 3,1%
UBM Barrier/Seed - Cu PVD deposition $2,95 1,9%
UBM Barrier/Seed - Reflow $0,90 0,6%
UBM Barrier/Seed - Cleaning $1,10 0,7%
UBM Barrier/Seed - Measurement $0,66 0,4%
Magnetic Concentrator - PR Deposition $3,85 2,5%
Magnetic Concentrator - Pattern $0,88 0,6%
Magnetic Concentrator - Cure thick resin $1,91 1,3%
Magnetic Concentrator - Cleaning $1,10 0,7%
Magnetic Concentrator - Measurement $0,66 0,4%
Magnetic Concentrator - Ni Deposition (16µm) $3,78 2,5%
Magnetic Concentrator - PR Removal $1,11 0,7%
Magnetic Concentrator - Cleaning $1,10 0,7%
Redistribution layer - PR Deposition $2,59 1,7%
Redistribution layer - Pattern $0,88 0,6%
Redistribution layer - Cure thick resin $1,91 1,3%
Redistribution layer - Cleaning $1,10 0,7%
Redistribution layer - Measurement $0,66 0,4%
Redistribution layer - Copper ECD 6µm $3,44 2,3%
Redistribution layer - PR Removal $1,11 0,7%
Redistribution layer - Cleaning $2,59 1,7%
Copper post - PR Deposition (Thick resin 50µm) $5,75 3,8%
Copper post - Pattern (Thick resin) $1,08 0,7%
Copper post - Cure thick resin $1,91 1,3%
Copper post - Cleaning $1,10 0,7%
Copper post - Measurement $0,66 0,4%
Copper post - Copper ECD 66µm $26,05 17,1%
Copper post - CMP $6,89 4,5%
Copper post - Cleaning (Thick resin) $11,02 7,2%
Copper post - PR Removal (Thick resin) $1,11 0,7%
Copper post - Measurement $0,66 0,4%
UBM etching - Copper etching (seed layer) $2,44 1,6%
UBM etching - TiN etching $2,59 1,7%
UBM etching - Cleaning $1,10 0,7%
UBM etching - Measurement $0,66 0,4%
Encapsulation layer - Epoxy deposition $9,73 6,4%
Encapsulation layer - Grinding $4,82 3,2%
Encapsulation layer - Cleaning $1,03 0,7%
Encapsulation layer - Measurement $0,66 0,4%
Encapsulation layer - Cu Etching $2,61 1,7%
Encapsulation layer - Cleaning $1,10 0,7%
Encapsulation layer - Measurement $0,66 0,4%
Additional BE - Backgrinding (300µm) $3,51 2,3%
Additional BE - Cleaning $1,10 0,7%
Additional BE - Laser Marking $4,63 3,0%
Additional BE - Cleaning $1,10 0,7%
Bumping - screenprinting $3,45 2,3%
Bumping - reflow $0,89 0,6%
Bumping - Cleaning $1,10 0,7%
Bumping - Measurement $0,66 0,4%
TOTAL $152,41
Packaging Steps Cost