Application of low temperature plasma equipment plasma power cleaning technology in LCD:
The COG assembly process of LCD is to mount the IC die on the ITO glass, and use the deformation and compression of the gold ball to connect the pins on the ITO glass with the pins on the IC chip. Due to the continuous development of fine circuit technology, it has been developed to produce products with a pitch of 20μm and a line of 10μm.
The production and assembly of these fine circuit electronic products requires very high surface cleanliness of TTO glass. The product is required to have good weldability, firm welding, and no organic or inorganic substances remaining on the ITO glass to prevent the continuity between the TTO electrode terminal and the ICBUMP. Therefore, the cleaning of the ITO glass is very important.
In the current ITO glass cleaning process, everyone is trying to use a variety of cleaning agents (alcohol cleaning, cotton swab + lemonade cleaning, ultrasonic cleaning) for cleaning, but the introduction of cleaning agents will lead to other problems caused by the introduction of cleaning agents. Therefore, exploring new cleaning methods has become the direction of efforts of various manufacturers. It is a more effective cleaning method to clean the surface of ITO glass by using low-temperature plasma equipment plasma power supply through step-by-step experiments.
Plasma is a collection of positively and negatively charged ions and electrons, and possibly some neutral atoms and molecules, which are generally electrically neutral in the macroscopic view. Plasma can be solid, liquid and gaseous. Ionized gas is a gaseous plasma. The basic process in plasma is the interaction between various charged particles under the action of electric and magnetic fields to cause a variety of effects.

In the plasma cleaning of the liquid crystal glass by the plasma power supply of the low-temperature plasma equipment, the activated gas used is oxygen plasma, which can remove oily dirt and organic pollutant particles, because the oxygen plasma can oxidize the organic matter and form a gas to be discharged. The yield rate of polarizing plate paste is enhanced, and the adhesion between the electrode end and the conductive film is also greatly improved, thereby improving the quality and stability of the product.
The plasma power cleaning technology of low-temperature plasma equipment is actually a high-precision dry cleaning equipment, and its cleaning range is nano-level organic and inorganic pollutants.
In plasma cleaning applications, low-pressure gas glow plasma is mainly used. Some non-polymeric inorganic gases (Ar, N2, H2, O2, etc.) are excited under high frequency and low pressure to produce active particles containing ions, excited state molecules, free radicals and other active particles. Generally, in plasma cleaning, activated gas can be divided into two types: one is plasma of inert gas (such as Ar, N2, etc.); the other is plasma of reactive gas (such as O2, H2, etc.). These active particles can react with surface materials, and excited molecules clean the activated surface.
The plasma generation principle of the plasma power supply of the low-temperature plasma equipment is as follows: apply a radio frequency voltage (frequency of about tens of megahertz) to a group of electrodes, and a high-frequency alternating electric field is formed between the electrodes. The gas in the area is excited by the alternating electric field to generate plasma body. The active plasma performs the dual effects of physical bombardment and chemical reaction on the surface of the object to be cleaned, so that the surface substance of the object to be cleaned becomes particles and gaseous substances, which are exhausted by vacuum to achieve the purpose of cleaning.
The level of LCD technology is developing rapidly, and the limits of LCD manufacturing technology are constantly being challenged and development has become a cutting-edge technology that represents advanced manufacturing technology. In the cleaning industry, the requirements for cleaning are getting higher and higher. Conventional cleaning can no longer meet the requirements. Plasma cleaning ideally solves these precision cleaning requirements and meets the current environmental protection situation.