Removing Microcontact Printed Alkanethiols
Original Publication Date: 2001-Oct-01
Included in the Prior Art Database: 2003-Jun-20
Two methods for removing microcontact printed alkanethiols are presented. Microcontact printing (MCP) is a technique which utilizes an inked, micropatterned stamp to print chemicals or biomolecules onto a substrate . The most important application of MCP is the printing of alkanethiols onto Au, Ag or Cu to form a self-assembled monolayer (SAM) in the regions of contact between the stamp and the substrate. In this case, the printed monolayer can protect its substrate from dissolution in an etch bath . MCP can be used to print and etch selectively a layer on a substrate. MCP can be used for microfabrication purposes. Examples are microfabrication of Au, Ag, Cu, Pt, Pd microstructures and microelectrodes, patterning a catalyst for electroless deposition, patterning Cu interconnects, etc. Many microfabrication processes involve many steps and it is desirable to remove a SAM which has been used in one step before proceeding to the next steps of this process for several reasons. A Pd catalyst patterned on a surface using MCP should be cleaned to remove the thiols present on its surface to be an active catalyst, for example. The thiols used to structure a Cu layer should be removed before adding the next layer to minimize device-integration problems (bad contacts or adhesion between layers, degassing of thiols during a subsequent fabrication step). A patterned surface on which the SAM is left might have undesirable wetting properties.