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AKMAK8973 and AK89743-Axis Electronic Compass

Process Review

Some of the information is this report may be covered by patents, mask and/or copyright protection. This report should not be taken as an inducement to infringe on these rights.

© 2009 Chipworks Inc.

This report is provided exclusively for the use of the purchasing organization. It can be freely copied and distributed within the purchasing organization, conditional upon the accompanying Chipworks accreditation remaining attached.

Distribution of the entire report outside of the purchasing organization is strictly forbidden. The use of portions of the document for the support of the purchasing organization’s corporate interest (e.g., licensing or marketing activities) is permitted, as defined by the fair use provisions of the copyright act. Accreditation to Chipworks must be attached to any portion of the reproduced information.

MPR-0910-80113999SJDWJM

Revision 1.0 Published: December 11, 2009

AKM AK8973 and AK8974 3-Axis Electronic Compass Process Review

AKM AK8973 and AK8974 3-Axis Electronic Compass Process Review

Table of Contents

1 Overview1.1 List of Figures1.2 List of Tables1.3 Company Profile1.4 Introduction1.5 AK8973 and AK8974 Device Summary and Comparison1.6 AK8973 Process Summary

2 AK8973 Package and Die2.1 Package2.2 Die2.3 Die Features2.4 Package Cross-Sectional Analysis

3 AK8973 Detailed Process Analysis3.1 General Structure3.2 Dielectrics3.3 Metals3.4 Vias and Contacts3.5 Transistors and Poly3.6 Isolation3.7 Wells and Substrate

4 AK8973 Magnetic Hall Sensor Analysis4.1 Plan View Layout Analysis4.2 Diagonal Cross-Sectional SCM and SEM Analyses4.3 SRP Analysis4.4 SIMS Analysis

5 AK8973 Critical Dimensions5.1 Horizontal Dimensions5.2 Vertical Dimensions

6 Appendix: AK8974 Comparative Device Analysis6.1 AK8974 Package6.2 AK8974 Die and Die Features6.3 AK8974 Basic Package Cross-Sectional Analysis6.4 AK8974 Basic Process Analysis

AKM AK8973 and AK8974 3-Axis Electronic Compass Process Review

7 References

8 Statement of Measurement Uncertainty and Scope Variation

About Chipworks

AKM AK8973 and AK8974 3-Axis Electronic Compass Overview 1-1

1 Overview

1.1 List of Figures1 Overview1.4.1 3-Axis Hall Sensor Structure

2 AK8973 Package and Die2.1.1 Package Top2.1.2 Package Bottom2.1.3 Plan-View Package X-Ray2.1.4 Side-View Package X-Ray A2.1.5 Side-View Package X-Ray B2.1.6 Plan-View Package X-Ray with Back Plane Removed2.2.1 Die Photograph2.2.2 Die Markings2.2.3 Die Photograph at Metal 1 Annotated with Functional Blocks2.2.4 Die Photograph at Substrate (Dark Field)2.2.5 Die Photograph at Metal 1 Annotated with Analysis Areas2.3.1 Die Corner A2.3.2 Die Corner B2.3.3 Die Corner C2.3.4 Die Corner D2.3.5 Minimum Pitch Bond Pads2.3.6 Bond Pad2.3.7 Resistors and Capacitors2.3.8 Bipolar Transistors2.3.9 Hall Sensors2.3.10 Mask Markings2.4.1 Package Cross Section Overview2.4.2 Die Edge – Optical2.4.3 Die Beneath Magnetic Concentrator – SEM2.4.4 SEM-EDS Analysis of Ag Loaded Die Attach2.4.5 Magnetic Concentrator – Optical2.4.6 Magnetic Concentrator Right Edge – Optical2.4.7 Magnetic Concentrator Left Edge – SEM2.4.8 Magnetic Concentrator Right Edge – SEM2.4.9 Die Coat – SEM2.4.10 SEM-EDS of FeNi Magnetic Concentrator2.4.11 SEM-EDS of Magnetic Concentrator Cu Pad

3 AK8973 Detailed Process Analysis3.1.1 General Die Structure3.1.2 Die Edge3.1.3 Die Seal3.1.4 Test Pad Edge3.1.5 Mask Mark

AKM AK8973 and AK8974 3-Axis Electronic Compass Overview 1-2

3.2.1 Passivation3.2.2 IMD 23.2.3 IMD 1 and PMD3.2.4 PMD and Isolation3.3.1 Minimum Pitch Metal 33.3.2 Minimum Pitch Metal 23.3.3 Minimum Pitch Metal 13.4.1 Minimum Pitch Via 23.4.2 Minimum Pitch Via 13.4.3 Minimum Pitch Contacts3.5.1 Minimum MOS Transistor3.5.2 Minimum Poly Pitch3.5.3 Poly-Poly Capacitor3.6.1 Minimum Width Isolation3.7.1 N-Well3.7.2 P-Well

4 AK8973 Magnetic Hall Sensor Analysis4.1.1 Magnetic Sensor4.1.2 Magnetic Sensor Detail 14.1.3 Magnetic Sensor Detail 24.1.4 Magnetic Sensor Detail 34.1.5 Magnetic Sensor Detail 44.1.6 Magnetic Sensor at Substrate4.1.7 Magnetic Hall Sensor Detail at Substrate4.1.8 Hall Sensor Device Detail at Substrate – SCM4.2.1 Diagonal Cross Section Overview – SEM4.2.2 Diagonal Cross Section Overview – SCM4.2.3 Diagonal Cross Section Detail – SEM4.2.4 Diagonal Cross Section Detail – SCM4.3.1 SRP Profile Location on Hall Sensor4.3.2 SRP Profile for Hall Sensor4.4.1 SIMS Profile Location on Hall Sensor4.4.2 SIMS Profile for Hall Sensor

6 Appendix: AK8974 Comparative Device Analysis6.1.1 AK8974 Package Top6.1.2 AK8974 Package Bottom6.1.3 AK8974 Plan-View Package X-Ray6.1.4 AK8974 Side-View X-Ray6.2.1 AK8974 Die Photograph6.2.2 AK8974 Die Markings6.2.3 AK8974 Die Corner6.2.4 AK8974 Minimum Pitch Bond Pads6.2.5 AK8974 Die Features6.2.6 AK8974 Magnetic Sensor

AKM AK8973 and AK8974 3-Axis Electronic Compass Overview 1-3

6.2.7 AK8974 Hall Sensor Detail6.2.8 AK8974 Hall Sensor at Substrate Detail6.3.1 AK8974 Package Cross Section Overview6.3.2 AK8974 Die Beneath Magnetic Concentrator – Optical6.3.3 AK8974 Magnetic Concentrator Right Edge – SEM6.4.1 General Structure6.4.2 Die Seal6.4.3 Poly-Poly Capacitor

AKM AK8973 and AK8974 3-Axis Electronic Compass Overview 1-4

1.2 List of Tables1 Overview1.4.1 AK8973 and AK8974 Sample Markings1.5.1 Device Summary and Comparison1.6.1 Summary of Major Process Findings for AK8973

2 AK8973 Package and Die2.2.1 Die Utilization2.3.1 Package and Die Horizontal Dimensions2.4.1 Package and Die Vertical Dimensions

3 AK8973 Detailed Process Analysis3.2.1 Dielectric Layer Thicknesses3.3.1 Minimum Metal Horizontal Dimensions3.3.2 Metal Layer Thicknesses3.4.1 Minimum Via Horizontal Dimensions3.5.1 Polysilicon Thicknesses3.5.2 Minimum Transistors and Polysilicon Horizontal Dimensions3.6.1 Isolation Horizontal Dimensions3.7.1 Wells and Substrate

4 AK8973 Magnetic Hall Sensor Analysis4.1.1 Magnetic Sensor Parameters and Horizontal Dimensions4.2.1 Magnetic Sensor Vertical Dimensions

5 AK8973 Critical Dimensions5.1.1 Package and Die Horizontal Dimensions5.1.2 Minimum Metal Horizontal Dimensions5.1.3 Minimum Via Horizontal Dimensions5.1.4 Minimum Transistors and Polysilicon Horizontal Dimensions5.1.5 Isolation Horizontal Dimensions5.1.6 Magnetic Sensor Parameters and Horizontal Dimensions5.2.1 Package and Die Vertical Dimensions5.2.2 Dielectric Layer Thicknesses5.2.3 Metal Layer Thicknesses5.2.4 Polysilicon Thicknesses5.2.5 Wells and Substrate5.2.6 Magnetic Sensor Vertical Dimensions

6 Appendix: AK8974 Comparative Device Analysis6.2.1 AK8974 Package and Die Horizontal Dimensions6.3.1 AK8974 Package and Die Vertical Dimensions

AKM AK8973 and AK8974 3-Axis Electronic Compass Statement of Measurement Uncertainty and Scope Variation 8-1

8 Statement of Measurement Uncertainty and Scope Variation

Statement of Measurement UncertaintyChipworks calibrates length measurements on its scanning electron microscopes (SEM), transmission electron microscope (TEM), and optical microscopes, using measurement standards that are traceable to the International System of Units (SI).

Our SEM/TEM cross-calibration standard was calibrated at the National Physical Laboratory (NPL) in the UK (Report Reference LR0304/E06050342/SEM4/190). This standard has a 146 ± 2 nm (± 1.4%) pitch, as certified by NPL. Chipworks regularly verifies that its SEM and TEM are calibrated to within ± 2% of this standard, over the full magnification ranges used. Fluctuations in the tool performance, coupled with variability in sample preparation, and random errors introduced during analyses of the micrographs, yield an expanded uncertainty of about ± 5%.

A stage micrometer, calibrated at the National Research Council of Canada (CNRC) (Report Reference LS-2005-0010), is used to calibrate Chipworks’ optical microscopes. This standard has an expanded uncertainty of 0.3 µm for the stage micrometer’s 100 µm pitch lines. Random errors, during analyses of optical micrographs, yield an expanded uncertainty of approximately ± 5% to the measurements.

The materials analysis reported in Chipworks reports is normally limited to approximate elemental composition, rather than stoichiometry, since calibration of our SEM and TEM based methods is not feasible. Chipworks will typically abbreviate, using only the elemental symbols, rather than full chemical formulae, usually starting with silicon or the metallic element, then in approximate order of decreasing atomic % (when known). Elemental labels on energy dispersive X-ray spectra (EDS) will be colored red for spurious peaks (elements not originally in sample). Elemental labels in blue correspond to interference from adjacent layers. Secondary ion mass spectrometry (SIMS) data may be calibrated for certain dopant elements, provided suitable standards were available.

Statement of Scope VariationDue to the nature of reverse engineering, there is a possibility of minor content variation in Chipworks’ standard reports. Chipworks has a defined table of contents for each standard report type. At a minimum, the defined content will be included in the report. However, depending on the nature of the analysis, additional information may be provided in a report, as value-added material for our customers.

AKMAK8974 Hall Sensor Analysis

Appendix for AKM AK8973 and AK8974 3-Axis Electronic Compass Process Review

AKM AK8974 Electronic Compass Hall Sensor Analysis 2

Some of the information is this report may be covered by patents, mask and/or copyright protection. This report should not be taken as an inducement to infringe on these rights.

© 2010 Chipworks Inc.

This report is provided exclusively for the use of the purchasing organization. It can be freely copied and distributed within the purchasing organization, conditional upon the accompanying Chipworks accreditation remaining attached.

Distribution of the entire report outside of the purchasing organization is strictly forbidden. The use of portions of the document for the support of the purchasing organization’s corporate interest (e.g., licensing or marketing activities) is permitted, as defined by the fair use provisions of the copyright act. Accreditation to Chipworks must be attached to any portion of the reproduced information.

MPR-0910-801 Appendix14282JMSDW

Revision 1 Published: March 29, 2010

AKM AK8974 Electronic Compass Hall Sensor Analysis 21

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