Shenzhen Olian OL-1500 Series Fully automatic COF FOF TFOF bonding Dispensing production line :
COF, which stands for Chip On Flex or Chip On Film, is a kind of IC packaging technology. It fixes integrated circuits (IC) on flexible printed circuit boards (FPC) and connects the chip with the flexible substrate circuit through thermocompression, so as to realize the interconnection between the chip and the circuit.
The COF bonding process is the process of connecting the display driver IC chip to the soft film carrier through the COF technology. It mainly uses the flip – chip eutectic method to bond the gold bumps on the display driver IC with the inner leads on the flexible substrate. This process can realize the electrical connection and mechanical fixation between the chip and the substrate, and is a key process in the manufacturing of LCD/OLED display modules.
COF bonding machine is a special equipment used to complete the COF bonding process. It can accurately position and bond the COF and the panel or PCB to ensure the quality and reliability of the connection. The machine usually has a variety of functions, such as ACF (Anisotropic Conductive Film) feeding, cutting, pasting, and precise alignment and pressure – bonding. It can be divided into semi – automatic and fully automatic types according to the degree of automation. The fully automatic COF bonding machine can realize the automatic feeding, positioning, bonding and other operations of COF and panel, which can greatly improve the production efficiency and product quality.
ACF, whose full name is Anisotropic Conductive Film, is a kind of adhesive film with special electrical conductivity. It is composed of conductive particles evenly distributed in the adhesive matrix. The characteristic of ACF is that it has obvious differences in the electrical conductivity in the Z – axis direction and the insulation resistance in the XY plane. When the Z – axis conductivity resistance value and the XY plane insulation resistance value exceed a certain ratio, it can be called good conductive anisotropy. In the COF bonding process, ACF plays a vital role. It can not only connect the electrodes of the IC chip and the substrate to achieve electrical conduction, but also avoid the short circuit between adjacent electrodes.
● Feeding: First, the COF and the panel or PCB that need to be bonded are automatically fed into the working area of the bonding machine.
● Positioning: The machine uses high – precision visual positioning systems, such as CCD cameras, to accurately locate the position of the COF and the panel to ensure that they are aligned.
● ACF Feeding and Cutting: The ACF material is fed into the machine, and according to the required length, it is cut by the cutting device.
● ACF Sticking: The cut ACF is accurately pasted on the corresponding position of the COF or the panel.
● Preliminary Pressing: After the ACF is pasted, a preliminary pressing is carried out to make the COF and the panel preliminarily bonded and ensure that the ACF is evenly distributed between them.
● Main Pressing: Under the action of a certain temperature and pressure, the main pressing is carried out. During this process, the ACF is dissolved and solidified, and the conductive particles in it are compressed to form a conductive path, so as to realize the electrical connection between the COF and the panel.
● Inspection: After the bonding is completed, the machine will carry out an inspection to check whether the bonding position is accurate, whether the electrical connection is good, and so on.
● Cleanliness: During the bonding process, it is necessary to ensure the cleanliness of the working environment and the surface of the materials to avoid the influence of impurities and dust on the bonding quality.
● Temperature and Pressure Control: The temperature and pressure during the bonding process need to be strictly controlled according to the process requirements. Improper temperature and pressure may lead to poor bonding or damage to the materials.
● Alignment Accuracy: The alignment accuracy between the COF and the panel is very important, and any deviation may lead to electrical connection failure. Therefore, the visual positioning system needs to be regularly calibrated and maintained.
● Material Storage: COF and ACF materials need to be stored under specific conditions, such as temperature, humidity, etc., to ensure their performance is not affected.
While Olian Automatic provides a comprehensive range of equipment, their solutions for COF bonding typically fall into the following categories, often integrated into production lines:
These are the core machines used for the actual bonding process.
○ Technology: They utilize advanced PLC + HMI (Programmable Logic Controller + Human Machine Interface) control systems for stability. The machines are equipped with high-precision servo motors and CCD visual alignment systems to achieve high accuracy.
○ Precision: Their equipment is designed to achieve high alignment accuracy (often within ±3μm to ±10μm range depending on the model and application), which is critical for high-resolution displays.
○ Control: They employ sophisticated temperature and pressure control algorithms to ensure consistent bonding quality. The bonding heads are typically made of high-quality materials like tungsten steel or SUS440C to ensure thermal uniformity.
Since ACF is essential for COF bonding, Olian also manufactures equipment dedicated to the precise application of ACF onto panels or FPCs.
○ Function: These machines handle the unwinding, tension control, cutting, and precise placement of the ACF tape.
○ Integration: They are often integrated as upstream modules in a COF bonding production line.
For higher efficiency, Olian Automatic provides integrated solutions that connect multiple processes.
○ Process Integration: A typical line might include: Panel Loading → Plasma Cleaning → ACF Attachment → COF Pre-bonding → COF Main Bonding → Post-Bonding Curing (if required) → AOI (Automated Optical Inspection) → Unloading.
○ Automation: These lines utilize robotic arms or conveyor systems to transfer products between stations, minimizing human intervention and maximizing throughput.
● High Precision: Utilizing finite element analysis (FEA) for thermal and mechanical design, their machines ensure high parallelism and temperature uniformity during the bonding process, which is vital for preventing stress damage to the delicate glass panels.
● Stability and Reliability: With years of experience in FPD technology, Oulian’s equipment is known for its stable performance in mass production environments.
● Customization: As a manufacturer of non-standard automation equipment, they can customize machines and production lines based on specific customer requirements, such as different panel sizes (from small mobile phone screens to large monitors) and specific process flows.
● Intellectual Property: The company holds multiple patents and software copyrights related to automation control, alignment algorithms, and mechanical structure design, ensuring their technology remains competitive.
Shenzhen Olian Automatic Equipment Co., Ltd. provides a robust portfolio of equipment for the COF bonding process. From standalone precision bonding heads to fully automated production lines.their solutions are designed to meet the demanding requirements of the modern display manufacturing industry, emphasizing precision, stability, and automation.
