Sapphire wafer polishing solution

Abstract

The invention discloses a sapphire wafer polishing solution which consists of the following components in percentage by weight: 20 to 30 percent of silica sol with solid content of 30 to 40 weight percent, 10 to 20 percent of alumina with a diameter of 80 to 200nm, 0.1 to 0.4 percent of organic base, 0.1 to 3 percent of a dispersing agent, 0.3 to 1 percent of nonylphenol polyethylene ether and the balance of de-ionized water. According to the sapphire wafer polishing solution, the silica sol and the alumina are compounded, so that the polishing speed is ensured, and machining scratches are avoided; furthermore, the nonylphenol polyethylene ether, the dispersing agent and the like are added to form a stable colloidal dispersion system to promote the full wetting of a polished wafer and a polishing pad and the stable and uniform distribution of the polishing solution between the polishing pad and the polishing wafer, so that the reaction rate of each part of the surface of the wafer can be balanced, and the polishing quality is ensured and improved; the sapphire wafer polishing solution can be used for the machining of a sapphire wafer.

Description

technical field [0001] The invention relates to a polishing liquid suitable for chemical mechanical polishing of sapphire wafers. Background technique [0002] As an important branch of the electronics industry, the LED industry has developed rapidly in recent years. LED can increase the luminous efficiency by nearly 10 times, and the service life is more than 20 times that of traditional lamps. It has the advantages of green and environmental protection. Because of its efficient and environmentally friendly products, it has been widely recognized and sought after by the market. [0003] Among them, as the core of LED products and the part with the largest added value, substrate materials play an important role in determining the stability and life of LED light sources, and are also an important direction for the development of my country's LED industry. There are only two kinds of substrates currently available for commercialization, namely sapphire and silicon carbide su...

AI Technical Summary

Problems solved by technology

However, the laser equipment is expensive, the polishing cost is high, and the research on laser polishing sapphire has just started, and the systematic research on the mechanism of cold polishing is still lacking.

If the sapphire substrate is processed improperly, it will cause surface scratches and subsurface damage on the workpiece, and these defects will affect the optical characteristics, and cause stress concentration on the surface of the workpiece, which will affect the life and reliability of the workpiece

[0005] At present, the batch processing technology of sapphire in China is still very immature. When producing sapphire substrates, the proportion of substrates with cracks and edge chipping is relatively high, accounting for 5% to 8% of the total. After grinding and The polishing and grinding rate that can be achieved in the polishing process is also very low, and many processed sapphire slices have heavy surface scratches, and about 20% of the sapphire slices have rough and deep marks on the surface, which need to be re-grinded and polished. It leads to rework, and some reworked sapphire sheets are prone to the phenomenon that the sapphire thickness is too thin due to excessive grinding and polishing, which greatly increases the cost of sapphire substrate processing