​ACF (Anisotropic Conductive Film) is an indispensable key material in LCD screen production.

     Many customers are confused about how LCD screens integrate driver ICs and flexible printed circuit boards to achieve proper display performance. Manager Liu, an engineer at Shenzhen Hongjia Technology, explains: A type of conductive adhesive, also known as ACF, is used in LCD screen production. ACF (Anisotropic Conductive Film) serves as a bridge connecting the LCD (LCD/OLED) screen and the driver circuitry (such as PCBs, flexible printed circuits (FPCs), and driver ICs). It is an essential key material for achieving ultra-thin, high-resolution displays in modern electronic devices. Its importance cannot be overstated.

Below, we will explain its importance in detail from several perspectives:

1. What is ACF? How does it work?

ACF is a thin film material composed of a large number of tiny conductive particles (usually gold-plated plastic or resin spheres) uniformly dispersed in a binder (such as epoxy resin).

Its core characteristic is anisotropic conductivity:

· Conductivity in the Z-axis (perpendicular to pressure): During the thermocompression bonding process, pressure and heat are applied, squeezing and solidifying the ACF. The conductive particles at the connection points (such as between the chip's bumps and the substrate's electrodes) are flattened, forming a stable electrical connection path. Current can only flow in this perpendicular direction.

· Insulation in the XY plane (horizontal): Because the conductive particles are randomly distributed and their number is precisely controlled, they do not touch each other horizontally, preventing short circuits and ensuring insulation between adjacent electrodes with extremely close spacing.

2. The Critical Role and Importance of ACF in LCD Production

a. Enabling High-Density Interconnection of Fine Circuits

Modern displays (especially smartphones and VR devices) are achieving increasingly higher resolutions (4K and 8K). This means that the number of pins (I/O) on driver ICs is increasing dramatically, while the pitch between them is shrinking (now reaching below 20 microns). Traditional soldering technologies are simply unable to cope with such fine connection requirements. ACF's anisotropic properties perfectly solve the problem of simultaneous connection and insulation of micron-level pitch electrodes.

b. Providing Mechanical Bonding and Physical Protection

After curing, ACF exhibits high bonding strength, securely bonding components such as driver ICs and FPCs to glass substrates. This not only provides an electrical connection but also crucial mechanical stability, resisting the vibration, shock, and bending stresses that devices experience during daily use. Furthermore, the cured adhesive seals and protects the connection points, preventing moisture, dust, and chemicals, thereby enhancing product reliability and lifespan.

c. Adaptable to Flexible Displays and Uniform Connections

In flexible OLED displays and wearable devices, connections must withstand repeated bending. Cured ACF exhibits a degree of flexibility, making it more adaptable to dynamic bending than traditional rigid solder joints and less prone to breakage, ensuring the durability of flexible devices.

d. Process Advantage: Low-Temperature Bonding

The ACF bonding process is typically completed at relatively low temperatures (180°C - 220°C) and within a short timeframe. This low-temperature process is crucial for temperature-sensitive glass substrates, OLED organic materials, and flexible plastic substrates, preventing material damage, deformation, and performance degradation caused by high temperatures.

e. Streamlining the production process and improving efficiency

ACF is typically provided as a roll-to-roll film, suitable for automated production. The attachment, alignment, and thermal compression bonding processes can be highly automated, significantly improving production efficiency, consistency, and yield.

3. What would happen without ACF?

Without ACF, modern display technology would be virtually impossible:

· High-resolution screens would be impossible: Pin pitches could not be reduced, and screen resolution would remain stagnant.

· Screen bezels would be extremely wide: More space would be required for traditional connectors or solder joints, making a "full-screen" design impossible.

· Reliability would be significantly reduced: Solder joints would be susceptible to cracking due to vibration, connectors could become loose, and device life would be shortened.

· Flexible displays would become impossible: Rigid soldering would be unsuitable for bendable screens.

4. If the ACF is not properly bonded to the LCD screen, bubbles can form at the connection between the driver IC or flexible circuit board and the LCD, resulting in poor display performance.

     In short, ACF conductive adhesive is a core technology in the production of modern LCD screens (especially high-end, high-resolution, and flexible screens). It is more than just a "glue"; it is a sophisticated electrical interconnect material. Its performance directly affects the connection reliability, yield rate, and ultimate performance of the display. Shenzhen Hongjia Technology has 12 years of professional research and development, production, and sales of 1.14-inch to 12.1-inch LCD screens and accompanying touch screens. Our products have served many Fortune 500 companies. The ACF we use is all genuine Japanese packaging and is produced using fully automated COG and FOG machines to ensure reliable and stable product quality. We welcome your inquiries by email. We will provide competitive pricing and one-stop customized so