Canon : The World of Canon CMOS Sensors


	Canon is one of a small number of companies that make steppers, which play a central role in the manufacture of semiconductor chips. Because CMOS sensors are produced using semiconductor manufacturing technology, Canon was able to take advantage of its original split exposure technology in the production of the 35mm full-frame CMOS sensor. That is how a large single-plate CMOS sensor was realized.


	Semiconductor chips are manufactured by transferring circuit patterns onto silicon wafers by means of a process called photolithography. To enable high image resolution, extremely fine circuit patterns need to be transferred onto CMOS sensors. Because a 35mm full-frame CMOS sensor is too large for all these fine circuit patterns to be transferred by conventional photolithography in one shot, Canon developed its propriety split exposure technology. By transferring superfine circuit patterns in two or three passes, we are able to cover the entire area of a 35mm full-frame sensor. This feat was possible only because Canon has its own original manufacturing equipment that has nanometer-level accuracy. The manufacturing process for the 35mm full-frame CMOS sensor is optimized by transferring in one pass the elements of the circuit patterns that do not require super precision.