What is MEMS

What is MEMS technology?

MEMS technology, invented in the 1980s, is a technology that uses a silicon-based semiconductor manufacturing process to create miniature mechanical and electronic systems, and was first used in the automotive and military industries. The devices made by MEMS process are miniaturized and intelligent, which meet the demand for low power consumption and high consistency in the process of collecting different dimensions and large amount of data from edge devices in IoT. However, before the birth of 4G network, the market demand for MEMS sensors was very limited due to the limited data transmission and carrying capacity of communication network, just like the human being in the fetal period, the development of the corresponding sensory organs will be limited because the neural network has not yet developed.

Throughout the history of the MEMS industry, the automotive industry, medical and health care industry, communications industry, and cell phones and game consoles and other personal electronic consumer industries have contributed to the rapid development of the MEMS industry. Especially since 2007, with the rapid popularity and development of consumer electronics represented by smartphones, the progress of MEMS commercialization has accelerated significantly. Thus, along with the birth of 4G networks and smartphones, MEMS devices have developed very significantly over the past decade or so, and according to IHS, the entire MEMS devices market will have a capacity of $16.5 billion by 2019, while a report by China ICT shows that the total global market for the downstream smart sensor market has reached $37.85 billion.

However, the entire MEMS device and downstream smart sensor market is still in the early stages of development, mainly because.

First, with the further improvement of data transmission speed and carrying capacity of 5G network and subsequent communication networks, the market demand for edge-end device sensing capability can only be further effectively generated, and the low power consumption, high consistency and micro-miniaturization of MEMS devices greatly fit this demand, and more emerging demand for MEMS devices and new application scenarios for existing MEMS devices will be continue to emerge in the next 10 years.

Second, the sensor is the core data portal of the Internet of Things (IoT), and the development of IoT drives the popularity of smart terminal devices, driving the growth of MEMS demand. According to GSMA statistics and forecasts, the number of global IoT devices is 12 billion in 2019 and is expected to grow to 24.6 billion by 2025, maintaining a compound growth rate of 12.7% from 2019 to 2026.

Third, the birth rate of the world's major industrial countries have declined to varying degrees in recent years, labor costs and the contradiction between supply and demand will further accentuate the demand for industrial manufacturing intelligence aimed at reducing the number of workers emerged, more and more manufacturing plants are experiencing intelligent transformation, and the application of MEMS sensors in the process of intelligent manufacturing is just in demand, demand will continue to rise.

Domestic MEMS enterprises with core technology will face unprecedented development opportunities in the next 10 years. First, China is the main concentration of consumer electronics, automotive, industrial manufacturing, which means that Chinese MEMS chip companies can establish closer ties with the downstream market. The foreign MEMS chip providers are mostly Infineon, STMicroelectronics, Texas Instruments, ADI and other large analog chip makers, as well as Bosch, Honeywell and other module manufacturers born from automotive and industrial manufacturing suppliers, the original pattern of interests in the enterprise system is more stable, compared to the domestic professional MEMS chip companies, its service awareness and service radius in close to the downstream have a certain disadvantage. Compared with domestic professional MEMS chip companies, they have certain disadvantages in terms of service awareness and service radius, and their response to new demands in new markets is relatively backward, while domestic manufacturers are more capable of grasping new disruptive demands in downstream markets. Therefore, this is a key reason for the long industrialization cycle of domestic MEMS products, and is also an important factor that international MEMS chip makers are still in the lead. The leading domestic MEMS chip companies in the manufacturing end of the investment will shorten the industrialization process of new products, greatly improving its competitiveness in the entire MEMS industry.

The basic characteristics of MEMS sensor chips

Unlike the standard CMOS production process for large-scale integrated circuit products, MEMS sensor chips are essentially a collection of miniaturized mechanical systems and integrated circuits manufactured on silicon wafers, requiring the integrated use of multidisciplinary, multi-industry knowledge and technology, production and processing processes are significantly non-standardized and highly customized, as well as the support of the product supply chain system has very high requirements. MEMS chips have very strong process characteristics, three-dimensional manufacturing process is very different from the two-dimensional manufacturing process of integrated circuits, which is also an important reason for the national 14th Five-Year Plan to explicitly include the breakthrough of MEMS special process.

What are the main technical thresholds

(1) Comprehensive application of cross-industry knowledge and technology

MEMS is an interdisciplinary discipline, the development and design of MEMS products require the accumulation and integration of interdisciplinary knowledge of mechanical, electronic, materials, semiconductor and other cross-industry technologies such as mechanical manufacturing, semiconductor manufacturing, etc. MEMS industry R & D and design personnel need to have the above expertise and in-depth understanding of upstream and downstream industries in order to design both to meet customer needs, and Therefore, the professional knowledge and industry experience of R&D personnel are highly required.

(2) There are technical barriers in each production process

Compared with the large-scale integrated circuit industry, the R&D steps of MEMS products are more complex. In addition to the design of MEMS sensor chips, we also need to develop MEMS wafer manufacturing processes that are suitable for the company's chip design route. In the absence of mature MEMS process modules from wafer manufacturers, the company needs to participate in the development of manufacturing process modules suitable for wafer manufacturers, and even in the case that wafer manufacturers already have mature manufacturing process modules, the company needs to determine the specific process flow for each chip according to the company's chip design route. Since MEMS sensors need to make contact with the external environment and sense changes in external signals, the packaging structure and packaging process of the finished product need to be developed and designed to reduce the possibility of product failure. As MEMS sensors undertake functions such as acquisition and conversion of external signals, with diverse downstream application scenarios and extremely small mechanical systems inside the product that are relatively sensitive to the external application environment, the company also needs to be responsible for the development of MEMS professional test equipment systems and test technologies to meet the demand for MEMS sensor product performance and quality testing. Therefore, the MEMS sensor industry in the chip design, wafer manufacturing, packaging and testing links have barriers.

(3) technology process non-standardized

MEMS sensor has a product a processing process characteristics. mEMS sensor products are diverse, a variety of products and applications are not the same, making a variety of MEMS sensor production processes and packaging processes need to be debugged according to product design, wafer and finished product testing process also takes a non-standard process, so the MEMS sensor products do not exist Therefore, there is no generalized technology process for MEMS sensor products, it needs to start from the basic research and development of product design, production process, equipment development and material selection and other production factors to experience a long period of research and development and investment, and in the process of shipping a large number of the above production factors to improve and optimize.

The development status of MEMS sensors

MEMS sensors have been widely used in various fields such as consumer electronics, automotive, industrial, medical, communication, etc. With the development of artificial intelligence and IoT technology, the application scenarios of MEMS sensors will be more diversified.MEMS sensors are one of the important underlying hardware for artificial intelligence, the richer and more accurate the data collected by sensors, the better the function of artificial intelligence will be.

The core of the IoT ecosystem is sensing, connectivity and computing, and with the continuous growth of connected nodes, the requirements for the number of intelligent sensors and the degree of intelligence are also rising. In the future, the smart home, industrial Internet, automotive networking, smart cities and other new industrial sectors will bring a broader market space for the MEMS sensor industry. Because of its unique advantages, MEMS sensor applications are by no means limited to wearable devices, the future of medical, artificial intelligence and automotive electronics and other areas of transmission underlying architecture are dependent on MEMS sensors to layout.

From the current global development trend, the automotive industry and consumer electronics market has developed enough to become the basis for the development of MEMS sensors. The future, medical, artificial intelligence, Internet of Things, smart cities and other application areas of intelligent modernization trend is obvious, the development potential of MEMS sensors is great.

Future technology development trends.

(1) MEMS and sensors show a trend of high integration and combination of multiple functions. As the design space, cost and power budget is increasingly tight, the integration of a variety of sensitive components on the same substrate, made to detect multiple parameters of the multifunctional combination of MEMS sensors become an important solution.

(2) sensor intelligence and edge computing. Software is becoming an important part of the MEMS sensor, with the further integration of a variety of sensors, more and more data need to be processed, the software makes a variety of data fusion is possible.

(3) sensor low-power and self-powered demand is increasing. With the rapid growth of the Internet of Things and other applications for sensing needs, the number of sensors used has increased sharply, and energy consumption will double. Reduce the power consumption of sensors, the use of environmental energy harvesting to achieve self-powered, enhanced range of demand will always accompany the development of sensors, and increasingly strong.

(4) MEMS to NEMS evolution. With the miniaturization of terminal devices, diversification of types, to promote the rapid development of microelectronics processing technology, especially nanometer processing technology, intelligent sensors to smaller size evolution is the trend. Similar to MEMS, NEMS (nano-electro-mechanical systems) is a micro-nano system technology focused on the field of nanoscale, only smaller size.

(5) The rise of new sensitive materials. Thin-film piezoelectric materials offer better process consistency, higher reliability, higher yields, and smaller areas for MEMS actuators, speakers, haptic and touch interfaces, etc. The drive mode of future MEMS devices is expected to shift from traditional electrostatic comb drive to piezoelectric drive.

(6) Larger wafer size. Compared to the industry's current common application of 6-inch, 8-inch wafer manufacturing process, larger wafer size can largely reduce costs and improve yields, and the expansion of wafer size and chip feature size reduction is corresponding to promote and promote each other. For example, MEMS products manufactured on 12-inch wafer process lines are already available. Translated with www.DeepL.com/Translator (free version)