Plowing on the Sub-50 nm Scale: Nanolithography Using Scanning Force Microscopy

Abstract

A new nanolithography technique based on mechanical surface deformation with the tip of a scanning force microscope is reported here. In the lithographic step, the furrow is dynamically plowed into the substrate (see Figure). The pattern transfer is then carried out in a separate wet chemical etching step, thus preserving the tip. The technique can provide linewidths as narrow as 20 nm.

AFM Tip Hammering Nanolithography

“…In this technique, an AFM tip with a radius of about 10 nm is employed to create features by machining the surface, inducing local modifications or reactions on the surface, or delivering molecules to the surface. The AFM nanolithography examples of “writing” nanopatterns with “polymeric paper” include mechanical force nanolithography,4–9 acoustical force nanolithography,10 electrostatic nanolithography,11–14 thermal‐mechanical nanolithography,15, 16 floating‐tip nanolithography,17 thermal‐chemical nanolithography,18 constructive nanolithography,19 polymerization nanolithography,20–22 and dip‐pen nanolithography (DPN) 23–25. Mechanical force nanolithography is based on the mechanical interactions between tip and substrate in either a static plowing or dynamic plowing way to fabricate nanopatterns.…”

“…Mechanical force nanolithography is based on the mechanical interactions between tip and substrate in either a static plowing or dynamic plowing way to fabricate nanopatterns. In static plowing,4, 5 the tip is operated in contact mode and scanned across the surface with a large loading force to generate features. In dynamic plowing,6–9 the surface is plowed with a vibrating tip in tapping mode.…”

Galvanic Deposition of Gold on GaAs: A Tip-Induced Lithography Approach

“…Subsequent exposure of the semiconductor surface to an Au(III) solution results in the deposition of gold by galvanic displacement reaction on pre-patterned defect areas. [16][17][18][19][20] have been demonstrated as useful approaches in the fabrication of metal structures on various surfaces.The metallization of semiconductor surfaces via the galvanic displacement reaction has been intensively investigated.2,21-23 Galvanic displacement deposition is a relatively simple redox reaction in which noble metal ions in solutions are reduced by the substrate resulting in growth of metal deposits with various surface morphologies. The surface morphology of electroless deposited metals depends on the substrate, composition of the electrolyte, including pH and conditions of deposition eg.…”

“…Subsequent exposure of the semiconductor surface to an Au(III) solution results in the deposition of gold by galvanic displacement reaction on pre-patterned defect areas. [16][17][18][19][20] have been demonstrated as useful approaches in the fabrication of metal structures on various surfaces.…”

“…Use of polymer masks to restrict reduction of gold on a specific area has been applied in most of static/dynamic plow-based lithography techniques. [16][17][18][19] In this work a simple three step process for a deposition of 50 nm wide and 10 nm high gold nanowires on GaAs semiconductor is described. This technique may allow the direct deposition of noble metals such as Au, Ag, or similar on GaAs semiconductor surface.…”