COB Bonding Procedure
一． Definition
Chip on Board (COB) refers to a kind of processing technique by which the IC is bonded with PCB.
二． Procedure
Step媳妇的弟弟怎么称呼Ⅰ. PCB Cleaning
Clean the PCB’s pad on which 田舍范成大the IC would be bonded with an erar, and then clean it again with the help of brush. At last, put the PCB on the aluminum plate in the same direction. If there are other components on the back of the PCB, foam should be put under it in ca that the components are destroyed. This step aims to prevent insufficient solder and provide convenience for following bonding.
StepⅡ. IC Attachment
Inject some red glue to the syringe and make sure it takes about 1/3 of the syringe’s capacity. Next, put right amount of red glue to the centre of the bonding ction and attach the IC lightly in the right direction. Meanwhile, the flatness and cleanness of the IC surface should be guaranteed.
StepⅢ. Bonding
治病救人After adjustment of the bonding machine’s technical data and central point疯疯癫癫, as well as the power of IC and PCB, put the PCB attached with IC on the proper place of the machine to conduct the bonding process and then u microscope to check the quality of soldering points, including size, length and the end of the line.
StepⅣ. Testing
Test the product on the basis of engineering requirement with the testing machine to check if there are any defections, such as messy code, half display, no display and so on. If some defective products are found, the maintaining will be conducted as soon as possible. The product should not be put into next procedure汽车电脑维修 until普尔塔龙新年好用英语怎么说 it’s tested to be perfect.
StepⅤ. Sealing and Baking
Put more than two pieces of bonded products on preheating board so that the glue to be aled later can distribute well on the proper place. A few conds later, conduct the aling process with machine or by hand with the purpo of preventing the IC, aluminum wire and pad to be oxidized. During the process of baking, the temperature should be adjusted to 125℃±10℃ and the process should last for 50 to 70 minutes for curing.
StepⅥ: Testing
Test the final products again and maintain the defective products from the first procedure.
Step指甲月牙代表什么意思Ⅶ: Coding
Code the qualified products with the inkjet printer according to the customer’s requirements.
