Phase gratings made with inductively coupled plasma technology

摘要

Inductively coupled plasma (ICP) equipment is a new advanced version of dry-etching equipment that has not been widely reported to produce micro-optical elements before. The obvious structural improvement of ICP over the usual widely-used Reactive Ion Etching (RIE) is that two Radio Frequency (RF) power sources are used in ICP, while only one RF power source is used in RIE. This structural improvement of ICP results in the features of high-density plasma, low pressure and good directionality of ions, thereby bringing us the advantages over RIE technology as the weaker surface damage, better vertical profile of the etched surface, smaller linewidth and more freedoms to control the etching process. In this paper we report our detailed experimental results of using the new ICP setup for producing microoptical elements. Experimental results support the view that ICP is a new advanced version of dry etching equipment for producing microoptical elements. Phase gratings made with ICP have wide applications in micro-optical elements and systems. It is believed that use of ICP is the new developing direction for fabrication of microoptical elements and systems in the future.