Third, waxless substrate.
To polish a wafer on a machine, there must be a carrier that can hold it, and the waxless substrate plays this role. The wafers to be processed are put on it one by one for processing. Therefore, the substrate must be selected with good wear resistance, not easy to degumming, and high-temperature resistance.
Fourth, the temperature.
As we all know, a chemical reaction must reach the appropriate temperature to occur, and too high or too low temperature may make the reaction invalid. Our polished sapphire wafer is chemical mechanical polishing. Only by first softening the wafer can the purpose of grinding be achieved through mechanical friction. And only if the size is worn off, the thickness is uniform, and the surface is basically flawless, it is inspected on the upper layer of various inspection instruments to meet the requirements of no visible scratches, corrosion pits, and all indicators. How to select the best polishing temperature will directly affect the polishing rate, the amount of polishing liquid used, and the consumption rate of consumables.
In addition to the above, there are various factors, such as personnel training, polishing pressure, rotating time. CRYSCORE will not summarize them one by one. In a word, the polished sapphire wafer is a process that requires all aspects to achieve the best configuration, because it requires perfection and no defects. As long as one factor is unreasonable, it may lead to a situation of total failure.