The Innovative Calibration Method on Large Area Mask Exposure Machine
|關鍵字:||標準片;大尺寸光罩;大尺寸光罩曝光機;校正;Golden Plate;Large Area Mask;Large Area Mask Exposure Machine;Fabrication;Calibration|
Currently, it is very expensive or hard to produce a full stage “golden plate” for large area mask fabricators to calibrate their stage of the exposure tool. Furthermore, it is lack of recessive calibration data or theoretical information for implementing calibration processes for the metrology tool to measure large area mask to meet the requirement of customers in semiconductor industry. Roughly, there are 2 reasons: First, it is very difficult to order or get the suitable “golden plate”. The price is too high. Second, the technology generation is pushed faster and faster. The lifetime of each generation becomes shorter and shorter. The “golden plate” of former generation tool is no lounger larger enough in full stage calibration for current generation tool to meet the requirements of large area mask customers. The research proposes a simple and practical methodology of metrology and calculation for large area mask exposure machine. The proposed innovative methodology was generated by many series of experimental tests and supported by least squcure statistical method. The metrology and verification software has been developed and evaluated based on large amount of measured data from on line metrology machine for about a year. Applying this methodology, the expected calibration performance shows that it is no longer limited by full stage “golden plate” for large area mask exposure machine. The big advantage is that the expensive metrology tool is not necessary the only choice for the calibration of large area mask exposure tool. Several experiment data results demonstrate and prove the methodology is accurate, reasonable and suitable on current higher accuracy exposure and metrology tools for IC masks. The proposed methodology has been applied to on line large area mask fabrication. The practical performance and the customer’s appreciated feed back have also demonstrated the efficiency and usefulness of the innovative metrology and calibration methodology.