The market’s thinnest 6-Axis IMU!
With the introduction of Apple’s latest products in Q4 2017, Bosch Sensortec is now the undisputed leader in MEMS IMU for consumer applications. Indeed, Bosch completely crushed the competition by replacing InvenSense inside the newest iPhone 8 and iPhone X, and supplanting STMicroelectronics for the Apple Watch Series 3. These three new design wins give Bosch hundreds of millions of unit sales per year.
This new Bosch Sensortec component is likely a custom 6-axis IMU made specifically for Apple. It is exactly the same component found inside the iPhone 8, iPhone X, and Apple Watch Series 3. One major improvement is the incredibly thin profile achieved by Bosch, with a total thickness of only 0.6mm compared to 0.9mm for the industry standard. This thickness was probably an Apple request in order to fit with the small form factor of the Apple Watch Series 3’s cellular functionality. To achieve this low profile, Bosch changed the packaging structure used for its preceding product, the BMI160.
On the design side, Bosch Sensortec made significant changes - particularly for the accelerometer, where the old single-mass structure was abandoned for a new structure achieving better sensing properties. The micromachining manufacturing process, unchanged by Bosch Sensortec for many years, was also revised, with a new process for both accelerometer and gyroscope.
Finally, a new ASIC die was designed to fuse the data from the accelerometer and gyroscope, and probably to deliver even lower current consumption and other functionalities.
This report includes a detailed physical analysis, with process description and manufacturing cost analysis. A complete comparison with Bosch Sensortec’s BMI160 is also provided, along with a comparison with InvenSense and STMicroelectronics’ latest 6-axis IMUs.
> Executive Summary
> Reverse Costing Methodology
> Bosch Sensortec
> Consumer IMU Market
> Apple iPhone X, iPhone 8, and Watch Series 3 Teardown
- View and dimensions
- Wire bonding process
> ASIC Die
- ASIC die view and dimensions
- ASIC delayering and main blocs
- ASIC die process
- ASIC die cross-section
> MEMS Accelerometer Die
- MEMS die view and dimensions
- MEMS die cross-section
- MEMS accelerometer process
> MEMS Gyroscope Die
- MEMS gyroscope process
> Physical Comparison
- Bosch IMU sensor evolution
- Comparison with IMUs from InvenSense and STMicroelectronics
Sensor Manufacturing Process
> MEMS Accelerometer Process and Fabrication Unit
> MEMS Gyroscope Process and Fabrication Unit
> Packaging and Final Test Fabrication Units
> Synthesis of the Cost Analysis
> Yields Explanation and Hypotheses
> ASIC Component
- Wafer front-end cost, probe test, thinning and dicing
- ASIC wafer and die cost
- Wafer front-end cost, probe test and dicing
- Accelerometer wafer and die cost
- Gyroscope wafer and die cost
> LGA Packaged Component
- Back end: LGA packaging cost
- Back end: final test
- Component cost
ABOUT SYSTEM PLUS CONSULTING
System Plus Consulting specializes in the cost analysis of electronics, from semiconductor devices to electronic systems.
Created more than 20 years ago, System Plus Consulting has developed a complete range of services, costing tools and reports to deliver in-depth production cost studies and estimate the objective selling price of a product.
System Plus Consulting engineers are experts in:
Through hundreds of analyses performed each year, System Plus Consulting offers deep added-value reports to help its customers understand their production processes and determine production costs. Based on System Plus Consulting’s results, manufacturers are able to compare their production costs to those of competitors.
System Plus Consulting is a sister company of Yole Développement.
More info at www.systemplus.fr
Manufacturing process flow
Supply chain evaluation
Manufacturing cost analysis
Estimated sales price
Comparison with Bosch’s BMI160 6-Axis IMU (Bosch Evolution)
Comparison with InvenSense and STMicroelectronics’6-Axis IMUs