Electronic components are divided into two categories, active and passive, the difference lies in whether or not power is required to drive. Semiconductor components such as transistors and diodes are often discussed as active components; passive components including resistors, capacitors, inductors, etc. are often regarded as supporting roles on the motherboard. In recent years, the phenomenon of short supply of passive components in the market has attracted market attention, especially MLCC for the most part, MLCC is a kind of ceramic capacitor. Its capacitance value is proportional to the surface area of the product and the number of layers of ceramic film stacking. Due to the progress of ceramic film stacking technology, the capacitance value content is also higher, and it can gradually replace medium and low capacitors such as electrolysis market applications for capacitors and tantalum capacitors.
In recent years, the shortage of passive components in the market has attracted market attention, especially MLCCs, but what are the functions of these electronic components?
Electronic components are divided into two categories, active and passive, the difference lies in whether or not power is required to drive. Semiconductor components such as transistors and diodes are often discussed as active components; passive components including resistors, capacitors, inductors, etc. are often regarded as supporting roles on the motherboard, and non-related professionals rarely understand them. However, their technological development also very important.
The function of the resistor is mainly to adjust the current and voltage, and the inductor is to filter the current noise, prevent electromagnetic interference, and stabilize the current. Capacitors are the main electrical energy storage components on the board, performing functions such as coupling and coordination. Among the three passive components, capacitors have the largest market size, which can be divided into ceramic capacitors, aluminum capacitors and tantalum capacitors. Currently, the most popular MLCC is Multi-layer Ceramic Capacitor, also known as Multi-layer Ceramic Capacitor.
Characteristics of Passive Components
The capacitance value of multilayer ceramic capacitors is proportional to the product surface area and the number of stacked layers of ceramic films, and the product code is usually divided by the package size. However, due to the advancement of ceramic film stacking technology, the smaller the volume, the smaller the capacitance value may not be, and MLCC began to replace electrolytic capacitors and tantalum capacitors. Of course, the latter two still occupy a considerable market share, and each has its own advantages. However, with the popularization of high-performance consumer electronic products such as personal computers and smart phones, the demand for MLCC Also getting bigger.
Ceramic capacitors are favored because of their physical properties such as high voltage resistance, high heat, wide operating temperature range, and low loss rate when used at high frequencies, and can be chipped to reduce volume, low price, and high stability. It is very suitable for mass production. Although the capacitance value of aluminum capacitors is high, and the degree of chipization is second only to MLCCs, the performance is more affected by the environment. Tantalum capacitors also have the advantages of DC bias and stable capacitance, low leakage loss, and pressure resistance to substrate deflection, but they have more pollution problems and are more expensive.
In fact, not only traditional electronic products need passive components, but the automotive industry also needs passive components. Especially in recent years, new products such as electric vehicles and self-driving cars have become popular. In the past, a car required nearly 2,000 passive components. There are designs as high as nearly 10,000 pieces, and the demand cannot be underestimated. Not only MLCC, but it is also rumored that the delivery time of aluminum capacitors has been extended to more than half a year. It can be said that the market is quite short. At present, the main supplier of passive components in the world is Japan. Although Taiwan is the second largest supplier of passive components, the relevant industry mainly focuses on passive component production, little investment in upstream material development. Nearly 70% of materials such as interface ceramic powder, ceramic substrates, alumina substrates, quartz substrates, conductive adhesives, and cathode foils are also from Japan.
What is Multilayer Ceramic Capacitors (MLCC)?
Multi-layer Ceramic Capacitor (MLCC) is a kind of ceramic capacitor. Ceramic capacitors are divided into single-layer ceramic capacitors and multilayer ceramic capacitors (MLCC). Due to the advancement of ceramic film stacking technology, the capacitance content is also higher, and it can gradually replace the market application of low-to-medium capacitors such as electrolytic capacitors and tantalum capacitors, and MLCC can be directly attached through SMT, and the production speed is faster than electrolytic capacitors and tantalum capacitors. Fast, coupled with the characteristics of 3C electronic products becoming light, thin and short, MLCC is easy to chip and has the advantages of small size, and has become the mainstream product of the capacitor industry, accounting for about 43% of the output value of capacitors, followed by aluminum electrolytic capacitors, about 32%.
MLCC has physical properties such as high voltage resistance and high heat resistance, wide operating temperature range, and can be chipped to make it small in size, large in capacitance, good in frequency characteristics, low in loss rate when used at high frequencies, suitable for mass production, low in price and stable. High advantages, the disadvantage is that the capacitance value is small, far less than that of aluminum electrolytic capacitors. However, due to the increasingly advanced ceramic film stacking technology, the content of the capacitance value is also higher, and the electrical characteristics are also continuously improved. It can replace the low capacitance value in application. Aluminum capacitors, and tantalum capacitors that are expensive and have pollution problems.
MLCC is composed of parallel ceramic materials and electrode materials. Its internal structure is: ceramic layers and internal metal electrode layers are alternately stacked, that is, each ceramic layer is sandwiched by two parallel electrodes up and down to form a flat capacitor, and then connect each capacitor in parallel by connecting the inner electrode and the outer electrode, so that the total storage capacity of the capacitor can be increased. The total capacitance of the multilayer ceramic capacitor is the sum of the capacitances, and the purpose of connecting the capacitors in parallel is to increase the capacitance or store the charge.
According to the material structure of MLCC, it is mainly divided into two aspects: dielectric ceramic powder and internal and external electrodes. The main raw material of dielectric ceramic powder is barium titanate. After adding various additives, it forms NPO, COG, Y5V, X7R, Z5U and other types. The application is also different according to the electrical characteristics. The dielectric ceramic powder determines the characteristics of MLCC. X7R, X5R and Y5V are high-capacitance values. In terms of grades, X5R and X7R are better than Y5V, while NPO is mainly used for communication products; in terms of price, for MLCCs of the same size and the same capacitance value, X7R≒X5R>Y5V >Y5U.
Another cost of MLCC that accounts for more than 35% of the production cost is the electrode metal. Because of the trend of increasing the speed of CPU and communication components of active components, the number of layers of MLCC must also be increased. Each additional layer of MLCC is added. It is necessary to coat a layer of internal electrodes, and the number of layers of palladium metal usage has also increased rapidly. Since palladium metal is a rare and precious metal, the price is quite expensive, and the main supply is from Russia. Insufficient and out of stock, so the industry replaces the current palladium metal electrode material with base metal (nickel, copper) and other metals, hoping to reduce the cost by nearly 30% through the BME (base metal) process.
MLCC has a variety of different specifications, and the difference between each product mainly lies in the capacitance value (storage power per unit voltage), size (above 1210, 0805, 0603, 0402, 0201 and other specifications), temperature stability (Y5V, X7R and NPO, etc.), upper limit of operating voltage, safety certification, ESR (capacitance/time required for charging and discharging) and Q value (the degree of loss of input energy). Taking temperature stability as an example, MLCC will have different temperature stability due to the difference of the main raw material dielectric ceramic powder. Among them, Y5V type MLCC has the lowest unit capacitance cost, X7R is the second, and NPO is the highest. Due to the low technical difficulty of production, low price and many competitors, the MLCC of X7R and X5R will gradually replace the Y5V type as portable electronic products require higher temperature stability.
MLCC can be divided into 0201, 0402, 0603, 0805 and larger than 1206 according to the size of the product. Type 0805 and type 0603 are mainly used for information products such as motherboards and notebook computers. Type 0402 and 0201 are mainly used in high-end mobile phones. With the trend of thin and light electronic products, the proportion of products with 0402 and 0201 specifications continues to increase, and the growth momentum comes from the demand for consumer electronic products such as iPod/iPhone, game consoles and LCD TVs.
Major global suppliers of MLCC include: Japan's Murata Mfg (25% of the market), TDK (14%), Taiyo Yuden (8%), Kyocera, Panasonic, and Taiwan's Yageo (13%), Walsin Technology (13%), Walsin Technology (13%) 11%), Holystone, Honey Hope Honesty, Darfon, and mainland China’s Fenghua. Japanese manufacturers mainly focus on high-capacity MLCCs. Taiwan's Yageo and Walsin Technology mainly produce medium-to-low-capacity products in bulk specifications, while Holystone mainly produces niche-type high-voltage and high-capacity MLCCs.