Method for selective electroless attachment of contacts to electrochemically-active molecules

Abstract

A solution-based method for attaching metal contacts to molecular films is described. The metal contacts are attached to functional groups on individual molecules in the molecular film. The chemical state of the functional group is controlled to induce electroless metal deposition preferentially at the functional group site. The functionalized molecules may also be patterned on a surface to give spatial control over the location of the metal contacts in a more complex structure. Spatial control is limited only by the ability to pattern the molecular film. To demonstrate the feasibility of this concept, self-assembled monolayers of model, molecular-electronic compounds have been prepared on gold surfaces, and these surfaces were subsequently exposed to electroless deposition plating baths. These samples exhibited selective metal contact attachment, even on patterned surfaces.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a divisional of U.S. patent application Ser. No. 10 / 246,148, entitled “Selective Electroless Attachment of Contacts to Electrochemically-Active Molecules,” filed Sep. 17, 2002 by Christopher Zangmeister and Roger Van Zee, which was based upon and claims the benefit of U.S. provisional application No. 60 / 359,623, entitled “Selective Electroless Attachment Of Contacts To Electrochemically-Active Molecules”, filed Feb. 26, 2002, the entire disclosure of which is herein specifically incorporated by reference for all that they disclose and teach.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention generally pertains to molecular electronics and more specifically to the formation of metal contacts connected to molecules and molecular films. [0004] 2. Description of the Background [0005] Nearly all modern electronic devices are based on the complementary metal-oxide-silicon field-effect ...

AI Technical Summary

Benefits of technology

[0013] The disclosed embodiments have numerous advantages over prior art. These include the elimination of additional process steps required to make the MF compatible with a vacuum environment and greater control over the chemical state of the MF. With the present embodiment, the chemical state of the MF can be readily varied in solution by changing variables such as pH and ionic strength. The increased control gained by producing the MF in solution greatly increases the type of physiochemical interactions that may be formed between the metal contact and the molecular layer. Additionally, ELD offers spatial control and precision at the required device densities necessary in molecular electronic applications. These advantages make the present embodiment suitable for applications in a variety of areas including, but not limited to, molecular electronics, electrical contacts, metal patterning and electroless deposition.

Problems solved by technology

Unfortunately, CMOS technology is beginning to show limits associated with the fundamental physical laws governing device performance and technical problems associated with manufacturing.

For example, amine or carboxylic acid functional groups decrease the extent of metal penetration through a MF when metal contacts are grown on top of the monolayer by evaporation that can cause degradation or shorting of the electrical contacts.

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