Mask aligner determines the precise size of the chip, and the designer designs the circuit of the chip, and then engraves the circuit on the chip through the mask aligner, and its scale is usually above micron level. Mask aligner is the most expensive and technically difficult equipment in chip production, because it determines the overall framework and function of the chip.
In fact, it is not difficult to produce high-precision chips, but the production speed is too slow. mask aligner can produce high-precision chips quickly, so it is very important. The light emitted by the mask aligner is used to expose a photoresist-coated sheet through a patterned photomask. When the photoresist is exposed, its properties will change, so that the pattern on the photomask can be copied to the sheet, so that the sheet has the function of electronic circuit diagram.
Alignment system
The manufacturing of high-precision alignment system needs nearly perfect precision mechanical technology, which is also one of the technical difficulties that domestic mask aligner can't reach. Many American and German brands of mask aligner have special patented mechanical technology designs. For example, Mycron &；; Q mask aligner adopts the patented technology of all-pneumatic bearing design, which effectively avoids the process error caused by mechanical friction of bearings.
Another technical problem of the alignment system is the alignment microscope. In order to enhance the vision of microscope, many high-end mask aligner adopt LED lighting. There are two sets of alignment systems with focusing function. Mainly 1 uses binocular double-field alignment for microscope body, eyepiece and objective lens (mask aligner usually provides eyepieces and objective lenses with different magnifications for users to combine).