Of course, the most advanced mask aligner is made by the Dutch company ASML. Due to patent restrictions, China can't buy mask aligner made in ASML. At present, mask aligner supporting 28nm process has been developed by Shanghai Microelectronics, and the first one was delivered to customers at the beginning of 20021. Although 28nm is equivalent to the level of Dutch ASML company ten years ago, it represents the highest-end technology in China at present.