Let's start with a brief introduction to MEMS sensors :
MEMS stands for Micro-Electro-Mechanical System. A micro-electro-mechanical system is a miniature device or system that can be mass-produced, integrating micro-mechanisms, micro-sensors, micro-actuators, signal processing and control circuits, and even interfaces, communication, and power supplies. You can think of it as using traditional semiconductor processes and materials, employing micrometer technology to fabricate micromechanical components on a chip, and integrating them with corresponding circuits into a single unit. Therefore, it is an advanced manufacturing technology platform developed based on semiconductor manufacturing technology.
Advantages: Compared to traditional machinery, they are much smaller, with the largest not exceeding one centimeter and some even only a few micrometers in size, and their thickness is even smaller. They are made primarily of silicon, which has excellent electrical properties. Silicon's strength, hardness, and Young's modulus are comparable to iron, its density is similar to aluminum, and its thermal conductivity is close to that of molybdenum and tungsten. Employing manufacturing technologies similar to integrated circuits (ICs), they can utilize mature technologies and processes from IC production for large-scale, low-cost production, significantly improving cost-effectiveness compared to traditional "mechanical" manufacturing technologies.
Traditional electret microphones:
MEMS microphones:
If the preceding text wasn't clear, you can see from the images of the traditional microphone and MEMS microphone above that all the previous seven or eight mechanical components are integrated into a very small MEMS sensor chip. Therefore, its size is extremely small and its weight is very light. Because it's chip-manufactured, it offers good consistency, low power consumption, and is easier to mass-produce. However, this requires very high technical expertise.
The emergence of MEMS sensors has greatly satisfied everyone's requirements for small size and high performance in products.
MEMS sensor classification:
MEMS sensors come in many types and can be classified in many ways. Below is a classification based on their working principle:
Each type of MEMS sensor has many subcategories. For example, accelerometers, classified by the motion of the detected mass, include angular vibration accelerometers and linear vibration accelerometers, among many others. Common MEMS sensors include pressure sensors, accelerometers, micromechanical gyroscopes, inertial sensors, MEMS silicon microphones, and so on. The variety of MEMS sensors is so vast that it can be measured in tens of thousands, with numerous parameters varying between different MEMS types, and no completely standardized manufacturing process. This industry characteristic leads to excessively high upfront R&D investment for MEMS sensor manufacturers, making it difficult to scale up sales of a single product. Taking inertial sensors as an example, the break-even point for the market is 10 million units per month. This means that a company must produce at least 10 million inertial sensors per month to break even. According to surveys, the vast majority of domestic companies are far below this scale. MEMSensing, the largest pure MEMS sensor company in China, is still operating at a loss. Therefore, only the larger a company becomes can its profitability increase.
Applications of MEMS sensors:
MEMS sensors, as key components for information acquisition, have played a significant role in promoting the miniaturization of various sensing devices and have been widely used in fields such as space satellites, launch vehicles, aerospace equipment, aircraft, various vehicles, biomedical products, and consumer electronics. A typical application of MEMS sensors is shown in the figure below.
In smartphones, MEMS sensors offer a wide range of applications, including sound performance, scene transitions, gesture recognition, orientation tracking, and temperature/pressure/humidity sensing. In automobiles, MEMS sensors enhance vehicle performance through airbag collision sensors, tire pressure monitoring systems (TPMS), and vehicle stability control. In the medical field, MEMS sensors have enabled the development of miniature insulin pumps, making heart bypass surgery and artificial cell tissues practical treatments. In wearable applications, MEMS sensors enable motion tracking, heart rate measurement, and more.
Typical applications of MEMS sensors:
With the development of electronic technology, the application fields of MEMS are becoming increasingly widespread, expanding from early industrial and military aerospace applications to the general consumer market. Military and aerospace applications are considered high-value MEMS application areas, but the usage in these two fields is relatively small, only around $40 million annually, with limited growth potential. MEMS devices in medical electronics also have considerable value, with the average selling price of their sensors far exceeding that of other comparable MEMS sectors. Overall, the annual revenue of the high-value MEMS industry will reach approximately $300 million. However, the most widespread applications are in the automotive electronics industry and the consumer electronics market, these two sectors accounting for over 60% of the MEMS sensor market. We will analyze these two main application areas below.
Automotive electronic MEMS sensors:
The automotive electronics industry is considered the driving force behind the first wave of MEMS sensor applications. The rapid development of MEMS sensor applications in automobiles mainly benefited from the comprehensive implementation of automotive safety regulations by governments worldwide (such as requiring all vehicles to adopt TPMS systems) and the trend towards intelligent vehicles. Globally, the average car contains 10 sensors, with high-end cars employing approximately 25 to 40 MEMS sensors. The more advanced the car, the more MEMS sensors are used; the BMW 740i alone has over 70. MEMS sensors meet the requirements of harsh automotive environments, high reliability, accurate precision, and low cost. Their applications and market demands include vehicle anti-lock braking systems (ABS), electronic stability programs (ESP), electronic suspension systems (ECS), electric parking brakes (EPB), hill start assist systems (HAS), tire pressure monitoring systems (EPMS), engine damping, vehicle tilt measurement, and internal vibration detection, among others.
Currently, pressure sensors, accelerometers, gyroscopes, and flow sensors account for 99% of automotive MEMS systems. Their five-year growth rates have consistently ranged from 3% to 12%. MEMS pressure sensors are the most widely used sensors in automobiles, with prices typically between $5 and $7. In the automotive sector, MEMS pressure sensor revenue was projected to reach $1.26 billion in 2013, representing 74% of the overall industry revenue that year. At least 18 automotive application areas will drive the growth of pressure sensors, including tire pressure, brake sensors in electronic stability control systems, side airbags, engine control related to increasingly stringent emission standards, atmospheric pressure, and exhaust gas recirculation pressure.
The five largest automotive MEMS applications by sales revenue, ranked in descending order, are: ESC, airbags, intake manifold absolute pressure (MAP), TPMS, and rollover detection.
Global automotive MEMS revenue forecast (in US$1 million)
Overall, China will remain the world's third-largest user of automotive MEMS sensors from 2010 to 2015, ahead of Japan and many countries listed in "Other Regions". North America will continue to hold the top spot, with Europe ranking second. Total automotive MEMS sales are projected to reach $3 billion in 2015, a 25% increase from $2.4 billion in 2012. China's automotive MEMS sensor growth is significantly faster than the global average. Sales in China are expected to reach $387.9 million in 2015, compared to $194.3 million in 2010.
Analysis of MEMS sensor manufacturers for automotive electronics:
Revenue (in millions of US dollars) of the top 10 automotive MEMS sensor suppliers in 2012
As shown in Table 1, Bosch's revenue from automotive MEMS reached $625 million in 2012, far exceeding Denso's $296 million, which ranked second. The combined revenue of the top 10 manufacturers was $2.1 billion, while the overall automotive MEMS industry revenue last year was $2.3 billion, meaning the top 10 manufacturers accounted for nearly 94% of the market share. Therefore, the industry concentration for automotive MEMS is extremely high. There are no manufacturers from China.
Bosch's success in automotive MEMS sensors stems not only from its high technological level and broad product line—making it not only the largest supplier of pressure sensors but also the leading supplier of MEMS for the low-pressure field—particularly in Electronic Stability Control (ESC) systems, where the company is a major supplier of accelerometers, gyroscopes, and pressure sensors. To keep pace with the trend, accelerometers and gyroscopes are being packaged together (combined sensors) to reduce the overall cost for ESC system manufacturers.
Consumer electronics MEMS sensors:
With the rapid development of the consumer electronics sector and the continuous emergence of product innovations, especially benefiting from the rapid development of smartphones and tablets, consumer electronics has replaced the automotive sector as the largest application market for MEMS.
A Yole Development Research report predicts that the global consumer electronics MEMS sensor market will grow at a CAGR of 18.5% between 2013 and 2018, reaching $6.4 billion by 2018.
MEMS sensors used in smartphones and tablets account for nearly 90% of the consumer electronics MEMS sensor market. The market size is projected to grow from $2.85 billion in 2013 to $6.4 billion in 2019, with shipments increasing from 5.8 billion units in 2013 to 18.9 billion units in 2019.
Global MEMS market for smartphones and tablets (Data source: Yole Development 2013/07)
MEMS sensors are used in consumer electronics for applications including motion/fall detection, navigation data compensation, gaming/human-computer interfaces, power management, GPS enhancement/blind spot elimination, speed/distance counting, and more. This gives them a penetration far exceeding that of traditional semiconductor chips, and these MEMS technologies have significantly improved the user experience. Among all fields, mobile phones are the largest application area for MEMS. The most widely used sensors are accelerometers, gyroscopes, and MEMS silicon microphones, with accelerometers being the largest application product in this market. Recently, gyroscopes have experienced rapid growth, becoming the second largest application product after accelerometers. MEMS microphone sales approached $1 billion in 2014, and IHS indicates that the global MEMS microphone market will maintain a compound annual growth rate (CAGR) of 18% for five consecutive years. There are also some MEMS sensors that are in the R&D stage or have just entered the market, such as magnetometers, fingerprint sensors, environmental sensors, and MEMS mobile phone cameras.
STMicroelectronics is the undisputed leader in the global consumer electronics and mobile device market. The company has held the top spot since 2009, and last year saw a robust 22% growth, capturing 27% of the overall market. Gyroscopes and accelerometers are its main products, but the concentration among the top manufacturers is significantly lower than in the automotive MEMS sector, primarily because the requirements for consumer MEMS are relatively lower.
Analysis of global MEMS sensor manufacturers:
IHS iSuppli releases its 2012 ranking of the world's top 20 MEMS suppliers.
In 2013, Bosch's MEMS sales grew by 26% to $1 billion, making it the world's largest MEMS supplier. Bosch is a well-known automotive MEMS supplier, with the automotive market accounting for 74% of its overall MEMS sales in 2013. IHS noted that Bosch's accelerometers not only dominate the Chinese smartphone market but also supply Apple's iPhone 5s and 5c, as well as the iPad Air. Furthermore, Bosch is the largest supplier of pressure sensors used in Samsung phones and tablets, and the company has begun mass production of 6-axis inertial measurement units (IMUs) that combine accelerometers and gyroscopes in a single package, supplying customers such as Sony, Samsung, and HTC.
IHS estimates that the global MEMS market reached $8.96 billion in sales in 2013. The top 20 MEMS suppliers globally generated $6.99 billion in revenue in 2013, accounting for 78% of the overall market. This concentration is very high. The list is dominated by European, American, and Japanese manufacturers. The only Chinese manufacturer on the list is AAC, ranked nineteenth, whose sales primarily come from MEMS silicon microphones.
The top 30 global MEMS sensor manufacturers, and the percentage of each manufacturer's products sold in mobile phones and tablets.
Because of the lower price requirements of MEMS sensors in consumer electronics, many manufacturers have not entered this application area, leaving opportunities for Chinese manufacturers in the future. Goertek, a Chinese company, ranks 29th, with its sales mainly coming from MEMS silicon microphones; it is the world's third-largest MEMS silicon microphone manufacturer. Another Chinese MEMS sensor manufacturer, MEMSensing Semiconductor, is not on the list. MEMSensing Semiconductor's 2012 sales were $64 million, which should be close to this ranking.
MEMS sensor market development trend
According to predictions by Yole Développement, a well-known US market research company, the MEMS sensor market reached $13 billion in 2014, and is expected to grow to $22.5 billion by 2018, with a compound annual growth rate of 12% to 13%, and a unit shipment volume of 2.35 billion.
The consumer application market reached $5.9 billion in 2014 and is projected to exceed $10 billion by 2019, representing a CAGR of approximately 11.2%. Consumer applications will remain the largest market for MEMS sensors in the future. The fastest-growing market is the medical market, which is expected to grow from $2.45 billion this year to approximately $7.2 billion in 2019, with a CAGR of nearly 30%!
In the next 5 to 10 years, the main application areas for consumer MEMS will still be smartphones and tablets. However, the application areas of MEMS will gradually expand to include emerging wearable devices and the Internet of Things (IoT). Although wearable devices currently account for a relatively small proportion, less than 10%, Apple, Samsung, and Huawei have already launched some wearable products, somewhat like the early days of smartphones. This market will definitely become the fastest-growing market for MEMS sensors in the future. Regarding the IoT, it may take 5 to 10 years for smart homes and smart cities to develop significantly, leading to substantial growth in MEMS sensor applications. However, before that, it's difficult to see significant development of MEMS sensors in the IoT field.
The high-value MEMS sensor market revenue increased to $1.6 billion in 2013 from $1.5 billion in 2012, and is expected to continue its growth trend in 2013, growing by 6.3% according to a report by market research firm IHS. Test and measurement, military and civilian aerospace, medical electronics, and industrial applications accounted for 80% of the high-value MEMS market revenue in 2013. The top ten high-value MEMS suppliers held just over 42% of the market share. Due to the highly fragmented nature of the high-value MEMS sensor market, 21 products can be used in over 100 different applications, leaving ample room for various integrators. After purchasing these MEMS semiconductors, integrators package them into sensors, with an average selling price reaching tens of thousands of dollars.
Note: Yole Développement's statistics are 30% larger than HIS's, but they assess the same growth trend. This does not affect our analysis.
Analysis of various future MEMS sensors:
Pressure sensors are widely used in the automotive and industrial markets, and with increasing demand from the consumer electronics market, they are poised to remain the largest segment of the MEMS market. Yole Développement analysts predict the MEMS pressure sensor market will reach $2 billion next year and surpass $3 billion in 2018. Smartphones utilize numerous MEMS devices, such as accelerometers, gyroscopes, silicon microphones, BAW filters, and duplexers. Biosensors and microflow sensors are also widely used and rapidly growing in the healthcare industry.
There is also a special type of sensor: the combined sensor. With technological advancements, performance requirements for products are increasing. For example, in indoor navigation, a solution using only an accelerometer can only accurately describe linear motion. However, if rotational motion (motion with turning changes) is required, designers need to use both a gyroscope and an accelerometer. Furthermore, a single product may have different functional requirements, necessitating the use of several MEMS sensors. With increasingly limited design space, combining MEMS sensor systems offers a natural advantage. Combined MEMS sensors can save costs (e.g., accelerometers and gyroscopes share an ASIC within a single package). As the demand for combined MEMS sensors in the consumer electronics market surges, the market growth rate for combined MEMS sensors will far exceed that of other MEMS devices. Major international companies such as InvenSense and STMicroelectronics have launched numerous combined sensors. Yole Développement predicts that the compound annual growth rate of combined MEMS sensors will reach 43% over the next six years, with the market size exceeding $2 billion by 2018.
According to a report by market research firm Yole Développement, driven by smartphone and microfluidic applications, emerging MEMS are projected to grow at a CAGR of 53% over the next six years, exceeding $2 billion in 2018 and accounting for 10% of the entire MEMS market. Yole Développement defines emerging MEMS as including: chemical and radiation sensors, scanning micromirrors, silicon-based microfluidics, MEMS switches, touchscreens, AOC MEMS, IDMEMS, energy harvesters, microdisplays, ultrasonic MEMS, joysticks, and micro fuel cells.
Market Forecast for Various Types of MEMS Sensors, 2013-2019
Analysis of the Development Trend of MEMS Sensors in China:
As the world's largest electronics manufacturing base, China consumes a quarter of the world's MEMS devices, attracting global attention. However, currently, China still relies heavily on imports for most MEMS and sensors. In 2013, only three Chinese manufacturers were among the world's top 50 MEMS suppliers: AAC, Goertek, and MEMS. Even AAC, the highest-ranked, had sales exceeding $100 million. However, in the last six or seven years, there has been a surge in domestic research and development of MEMS inertial sensors, especially between 2005 and 2008, with most research concentrated in top domestic research institutions such as Tsinghua University, Peking University, the Chinese Academy of Sciences, and the 26th Research Institute of Electronics. Several overseas returnees have also established MEMS sensor companies such as MEMS Semiconductor, Suzhou Minxin Microelectronics, and ShenDi Semiconductor (Shanghai) Co., Ltd. China's MEMS industry ecosystem is gradually improving, with a basic industrial chain formed from R&D, development, design, foundry, packaging and testing to applications. R&D centers have been established in Shanghai, Suzhou, and Wuxi. Although these MEMS companies have low shipment volumes, they still possess some competitiveness in some low-end consumer markets. MEMS microphone suppliers such as AAC, Goertek, and Gettop acquired Infineon's MEMS and ASIC chips and then packaged them themselves. MEMSIC produces accelerometers and magnetometers, Senodia produces magnetometers and gyroscopes, MiraMEMS produces accelerometers, magnetometers, and 6-axis electronic compasses, and QST produces accelerometers and magnetometers.
The application of MEMS sensors in the consumer market has gradually expanded from the high-end market to some low-end mobile phones and wearable devices. This market segment has a large future potential. Due to the technological gap between Chinese MEMS companies and major international companies, they will focus their efforts on the low-end consumer MEMS sector. They will remain highly competitive in these less demanding areas.
MEMS front-end R&D requires significant capital and time, and the sheer number of product types makes it difficult for MEMS devices to be profitable. Companies like MEMS and Suzhou Minxin Microelectronics, which design MEMS chips, are still unprofitable. The ultimate fate of these manufacturers will be either to succeed in the low-end consumer market or to accumulate technology and eventually be acquired by companies like Goertek.
Support from China's MEMS sensor industry policies
MEMS sensors belong to the integrated circuit industry. The central and local governments have begun to vigorously support the integrated circuit (chip) industry, which is unprecedented in terms of both funding scale and support strategy.
1. On March 5, Premier Li Keqiang mentioned the integrated circuit (chip) industry for the first time in his government work report at this year's Two Sessions.
2. On March 4th, the Shanghai Municipal Commission of Economy and Information Technology launched a special reward program for integrated circuit designers. Furthermore, Jiangsu, Shenzhen, and other provinces and cities are likely to introduce multi-billion yuan industry funds after the Two Sessions, led by the government and attracting social capital.
3. In June 2014, the State Council issued the "National Integrated Circuit Industry Development Promotion Outline".
4. On April 23, 2014, the state established a 120 billion yuan national-level chip industry support fund.
