摘要: | 傳統的繞射光罩製作技術大多利用二階(binary)光罩製作出多階的繞射元件,藉由多重曝光顯微技術以提昇繞射元件的光學效率,然將會造成製程上的煩瑣及繞射元件的誤差,若能直接製作出多階(multi-level)或灰階(grey-level)光罩,將會改善這些誤差的困擾。 國內對於灰階光罩的製程及機台尚屬於起步的研究階段,因此在本論文主要為研發灰階光罩的製作機台,名為光強調變雷射書寫機,並且利用此機台作實際的灰階光罩書寫並加以檢測,同時也將此灰階光罩經由半導體製程所製作出的成品加以量測比較,進而得知此機台所製作出的光罩是否達到要求,並以此來改善機台之精確性與可靠性,進而製作出符合需求的灰階光罩。 Traditionally, the diffractive optical element (ODE) is made by using the multiple binary-level lithography processes to enhance the diffractive efficiency. Due to the multiple exposures, the manufactory error will be included and more complicate processes is need to be considered. Therefore, to overcome these problems, the grey level mask can be used, in which only one exposure is needed to fabricate the optical element. This project presents that a laser machine with light intensity modulation to fabricate grey level masks. In the writer system, a solid-state laser with the power of 180 mw is used as the working light source. The processed target is laser direct write glass developed by the Canyon Material company. An acoustic-optics modulator (AOM) is used to modulate the laser intensity. To make sure the result of the processed mask, a measurement system is built. The laser direct writer system is already out of the binary methods to manufacture optical mask. The optical elements designer can use the LDW system to design any appropriate mask. Thus, the LDW system is a quite useful system for the ODEs. |