TDK: Detailed explanation of the future development of MLCC technology and materials

Central topics:

• Future development trends of MLCC technology and materials

Solution:

• MLCC packaging tends to be smaller and thinner

• MLCC performance is moving towards low ESL/ESR and high capacity

• Future technology development trends of MLCC

With the development of semiconductor integration technology, the integration of IC is getting higher and higher, and the use of components on the surface of circuit boards is decreasing. However, with the increase in the functions of various electronic devices, the trend of high-speed and low-power (low-voltage drive) semiconductor devices, the miniaturization of electronic modules and the increase in the number of interfaces, it is bound to cause electromagnetic interference in electronic circuits. In order to make the electronic circuits work normally and stably, it is necessary to add peripheral components to eliminate electromagnetic noise to ensure the normal operation of the circuit, which has increased the demand for passive components.

MLCC packaging tends to be smaller and thinner

The multifunctionality and miniaturization of home appliances such as mobile phones, laptops, game consoles, and LCD TVs have also put forward higher requirements for components such as capacitors, inductors, resistors, and connectors. In order to meet market demand and actively promote small and large-capacity applications, TDK is improving the layout of ultra-small MLCC product series from C0603 to C0402 sizes.

Compared with C0603, C0402 can save about 40~50% of the effective area of ​​the patch, and miniaturization can also reduce the parasitic inductance and parasitic resistance caused by wiring. Due to the reduction in size, the ESL (equivalent series inductance)/ESR (equivalent series resistance) of the component itself can become smaller, and it is also very beneficial to the high-frequency characteristics of the capacitor.

MLCC performance is moving towards lower ESL/ESR and higher capacity

In response to the trend of small, lightweight and multifunctional terminals such as PCs and mobile phones, in addition to the requirements of high-density patches, in order to meet the high performance and multifunctionality of electronic circuits, the operating frequency of LSI is getting higher and higher, which also puts higher requirements on low-impedance power supply. For mobile electronic terminal equipment such as mobile phones, in order to make the rechargeable battery last longer, the driving voltage will become lower and lower. At the same time, in order to prevent malfunction of the equipment, EMC countermeasures are becoming more and more important. The market demand for low-impedance, low-inductance ESR/ESL, small-size and large-capacity MLCC that can be used in a wide frequency (MHz~GHz) has become more urgent.

In electronic circuits, due to the influence of various noises, the voltage of the IC power supply line often changes, causing the IC device to not work properly. For high-speed computing semiconductor devices such as CPU, GPU, MPU, due to the increase in clock frequency, a relatively sudden voltage change will occur in the circuit. At this time, it is necessary to be able to work in a high-speed environment and stabilize the power supply voltage. This requires the configuration of high-capacity, low-impedance MLCCs around these high-frequency ICs that can eliminate noise and stabilize the power supply voltage. Due to the existence of ESR and ESL, the impedance of general capacitors increases with the increase of operating frequency. In design, a combination of capacitors suitable for different frequencies is generally used to correspond, which requires increasing the number of capacitors used, but this does not increase the bandwidth for suppressing noise. The high-capacity three-terminal MLCC series developed by TDK can reduce the number of capacitors used and improve the ability to suppress noise in high-frequency bands.

Portable terminals such as mobile phones and GPS have higher requirements for the volume, thickness and weight of MLCC. In order to meet the needs of this market, TDK has also launched an ultra-thin inverted MLCC series, which is only 0.35 mm thick and is very effective for low impedance in high-frequency bandwidth. On the other hand, the resonant frequency SRF of high-Q MLCC is relatively high, and it has very low impedance. When this high-Q MLCC combination is shared with IC, it will cause new noise.

Future Technology Development Trends of MLCC

The improvement of ceramic chip capacitor performance is mainly reflected in the following five aspects:

Electrical properties: The increase in capacity density per unit volume is due to the use of high dielectric constant materials, thin layers, and multilayers. At the same time, frequency response characteristics, DC bias voltage characteristics, and loss coefficient are also very important characteristics.

Function: The different requirements of application products put forward various functional requirements for MLCC, and the use of analog technology in the design of MLCC is also very important.

Reliability: Due to the diversity of application products, the operating temperature range and operating voltage of MLCC are becoming more and more demanding. Due to the acceleration of automotive electrification, the miniaturization, high performance and reliability of capacitors under high temperature and high voltage conditions are very important. At the same time, industrial electronic equipment requires MLCC to be resistant to high and low temperature shocks under very harsh conditions, have very high reliability, and be able to work normally and stably.

SMT patches: High-density mounting requires MLCC to have very high requirements in terms of size, shape, precision, terminal electrodes, and tape form. For example, TDK's narrow pitch tape is environmentally friendly and recyclable.

Price: With the development of MLCC towards miniaturization and high capacity and market competition, the price has dropped significantly in recent years. However, due to the increased difficulty of the manufacturing process, the miniaturization and thinning of the electrolyte have reduced the qualified rate of the products and increased the production cost. Of course, this contradiction between high performance and low price needs to be further resolved by manufacturers.

Material technology development trends

The most important factor supporting the development of MLCC is the development of material technology. Since 1991, the successful industrialization of MLCC internal electrodes from precious metals (Pd, Ag) to base metals (N) has led to rapid development in the miniaturization and capacity of MLCC. At the same time, thin-layer, multi-layer technology and design tolerance have also improved rapidly.

TDK is developing high dielectric constant materials at a rapid pace. The dielectric thickness is less than 1μm, the dielectric particle diameter is between 0.2~0.25μm, and the dielectric constant is between 3,800~4,000. The miniaturization of the dielectric is the basis for the thinning of the dielectric layer. Generally speaking, the miniaturization of the dielectric particles will lead to a decrease in the dielectric constant of the dielectric material, which is a difficulty in material design. In terms of material development, TDK uses highly crystalline barium titanate with BaTiO3 as the main material, making the miniaturization of the dielectric and the high dielectric constant possible.

The miniaturization and high performance of electronic equipment is the development trend of the electronics industry in the future. Due to the current economic situation, price competition is inevitable, which also puts higher requirements on MLCC manufacturers. The development of material technology, simulation technology, and manufacturing process technology will be a topic faced by all MLCC manufacturers.