EYANG Technology MLCC electrode displacement detection method

Eyang Technology's "Ultra-micro Multilayer Ceramic Capacitors for Mobile Internet" project won the "Second Prize for Scientific and Technological Progress of the 2017 China Electronics Society Science and Technology Award" awarded by the China Electronics Society. The award was officially presented by the China Electronics Society, and the conclusion of the appraisal of Eyang's scientific and technological achievements was: filling the domestic gap and reaching the advanced level of similar international products!

Ultra-miniature multilayer ceramic capacitors (MLCCs) are widely used in the new generation of electronic information technology products. They are typical basic components and also form the foundation of modern manufacturing. They have taken the lead in achieving nanoscale technological breakthroughs in the field of high-end passive components, which is of strategic significance for the upgrading and competitiveness of electronic information products.

In the printing process of ceramic components such as MLCC, the traditional printed pattern consists of the MLCC internal electrode (1), the short-axis blank margin (2) and the long-axis blank margin (3), as shown in the figure below. The printed film is stacked and cut to form a chip.

After cutting the two end faces of the chip, the internal electrode arrangement in the short axis direction can be seen, so as to quickly check whether there is short axis cutting deviation or short axis displacement. However, since the internal electrode arrangement in the long axis direction is blocked by the edge of the cut chip side, as shown in the figure below, it is impossible to directly check the internal electrode arrangement through the side appearance of the chip.

The current method of inspecting the arrangement of the internal electrodes in the long axis direction of the cut chip is to use a blade to cut the chip along the long axis direction, and then check whether the internal electrodes have long axis cutting deviation or long axis displacement. This long axis direction inspection operation is very cumbersome and inefficient, and there is a risk of long axis cutting deviation or long axis displacement flowing into the next process, which also affects product quality.

Therefore, in order to solve these problems and make up for the shortcomings, Yuyang Technology applied for an invention patent entitled "Printed screen, MLCC and detection method for rapid detection of electrode displacement" on June 28, 2016 (application number: 201610484312.3), and the applicant is Shenzhen Yuyang Technology Development Co., Ltd.

Based on the information currently disclosed in the patent, let us take a look at this electrode displacement detection technology.

As shown in the figure above, this is a top view of the printed screen for quickly detecting electrode displacement invented in this patent. It can be seen that: the main body of the screen is provided with a plurality of parallel and staggered internal electrode patterns 11, and an identification pattern 20 for detecting electrode displacement is provided between two adjacent internal electrode patterns along the short axis direction of the main body of the screen.

Thus, by adding an identification pattern between two adjacent inner electrode patterns in the short axis direction of the screen body, the identification pattern can be printed on the ceramic diaphragm simultaneously when printing the inner electrode, thereby forming a portion that can be used for identification.

After subsequent lamination and cutting, the identification part will be displayed on the side of the chip. Therefore, by detecting the graphic arrangement of the identification part, the alignment of the internal electrodes can be directly determined, thereby realizing rapid detection of cutting deviation or displacement of the short axis and long axis, greatly improving detection efficiency.

According to the schematic diagram of chip cutting printed by the printing screen for rapid detection of electrode displacement, it can be seen that the identification pattern is located at the intersection of the first blank margin and the second blank margin, and is not connected to the inner electrode pattern sub-units on both sides. For example, as shown in the figure, the identification pattern is a square, the side length of the identification pattern is less than or equal to the width of the second blank margin, and the number is 4-50.

The above figure is a three-dimensional schematic diagram of the chip stacking. It can be seen more clearly from the three-dimensional schematic diagram: when printing the inner electrode, the identification pattern will be simultaneously printed on the ceramic diaphragm to form the identification part, and then the ceramic diaphragm will be stacked and cut. After cutting, the chip identification pattern will be exposed at a fixed position on the end face and side of the ceramic chip.

Since the identification pattern is printed synchronously with the internal electrode, if the internal electrode is displaced in the long axis direction during printing, the side position of the identification pattern on the cut chip will change. Therefore, the electrode alignment can be used to quickly detect the electrode displacement and ensure product quality.

Finally, the figure above is a flow chart of the electrode displacement detection method. First, the internal electrode and the identification part are printed on the ceramic diaphragm at the same time according to the internal electrode pattern and the identification pattern, and then the ceramic diaphragm is repeatedly stacked and cut to form a ceramic chip after reaching the preset number of layers. Then it is determined whether the identification part is arranged at the preset position on the side of the ceramic chip: if so, the internal electrode arrangement is determined; if not, it is determined that the internal electrode has shifted.

The above is the detection method of electrode displacement of MLCC invented by Yuyang Technology. By setting the identification pattern on the printed screen and displaying it on the side of the chip after subsequent lamination and cutting, the alignment of the internal electrodes can be determined by only detecting the pattern arrangement of the identification part, and the short axis and long axis cutting deviation or displacement can be quickly detected, which greatly improves the detection efficiency and ensures product quality!