Current position:Technology Technology Details
1627

TFT LCD Glass Substrate Thinning Process

The thinning of the display glass substrateis mainly to use chemical etching and physical polishing to thin the panel and display glass to meet the needs of light and thin display products. The following panel application requirements can be achieved by thinning the 3.5 inch tft display panel .


1. Use chemical or physical methods to reduce the thickness of the glass substrateis  to achieve the purpose of thinning the panel.

2. Reduce the weight of the display screen; provide a clearer and brighter picture quality.

3. Reduce the occupied space, reduce the thickness of the module, and leave more space, such as increasing the battery capacity.

4. Make the glass substrate to a certain degree of flexibility, produce curved screens, and increase better visual effects.


image.png

TFT LCD Glass Substrate Thinning Process


1. Sealing process

Prevent the acid-base solution from entering the liquid crystal cell from the edge, destroying the frame sealant, entering the cell, and affecting product performance.


image.png

image.png



2. Etching and thinning process

Thinning principle method: 6HF+SiO2->H2SiF6+2H2O liquid+solid (glass)->liquid

image.png




Thinning method:


1. Multi-piece upright immersion type

image.png

Advantages: multiple pieces of glass can be processed at the same time.

Disadvantages: The device is large. There are sediments and white powder on the periphery, which are easy to adhere to the glass.




2. Single piece upright spray type

image.png

Advantages: It can meet different etching requirements on both sides. Multi-piece

Disadvantages: pits are easily generated on the etched surface.




3. Waterfall


image.png

Advantages: the surface is the smoothest, even without polishing

Main components of thinning process and equipment:

Process: Loader---Pre-cleaning---Etching---Cleaning---Drying---Unloader0.96 mono oled display equipment components: acid supply device, HF acid concentration meter, temperature controller, gas scrubber

image.png

Thinning process parameters

1. The relationship between reaction time and glass quality loss

2. The relationship between reaction rate and reaction temperature

3. The relationship between reaction rate and HF acid concentration

image.png


Explanation: (HF)2 is the most important active component in HF acid solution, because H-F bonds in the form of hydrogen bonds are more fragile than H-F bonds in HF molecules, and are easier to break when reacting with SiO2.


3. Grinding process

Process flow:

image.png

Poor thinning process itself

1. Do not wipe the dirt

image.png

2. Uneven thinning

image.png

3. Scratch after slimming

image.png

4. Poor B-ITO

Phenomenon: After the B-ITO of the ADS product is finished, the ITO in the contact position of the product and the BOX is severely corroded, which is similar to the mark left on the surface of the product after the water is dried.


Reason: BOX has a long-term turnover in the slimming workshop, and the acid gas in the slimming workshop has adhered to the surface of the BOX for a long time, which makes the surface of the BOX appear acidic.

image.png


5. Excessive resistance

Reason: acid residue


image.png

Sexual tolerance related to thinning

1. Shock and drop: Shock and drop the LCM. Perform display inspection and visual inspection on LCM.

2. Confirmation of the etching status of the glass substrate surface: Put it into a hot and cold tank with alternating hot and cold for display inspection of LCM and glass appearance inspection of TFT for microscope.

3. Confirmation of the corrosion status of the TFT terminal: continuous aging in a high-temperature and high-humidity aging tank. SEM observation and analysis of the surface and cross-section of the TFT terminal.


Hot reading

Latest News