Wafer-Scale Assembly of Semiconductor Nanowire Arrays by Contact Printing

TL;DR

This paper presents a simple contact printing method for wafer-scale, highly ordered, and uniform nanowire arrays, enabling scalable integration into electronic devices with controlled density and alignment.

Contribution

The study introduces a versatile contact printing technique for large-scale assembly of nanowire arrays with high uniformity and controllable density, advancing nanowire integration.

Findings

Achieved wafer-scale uniform nanowire arrays with ~95% alignment.

Controlled nanowire density up to ~8 NW/μm through surface treatment.

Enabled integration of nanowire arrays into various device structures.

Abstract

Controlled and uniform assembly of "bottom-up" nanowire (NW) materials with high scalability has been one of the significant bottleneck challenges facing the potential integration of nanowires for both nano and macro electronic circuit applications. Many efforts have focused on tackling this challenge, and while significant progress has been made, still most presented approaches lack either the desired controllability in the positioning of nanowires or the needed uniformity over large scales. Here, we demonstrate wafer-scale assembly of highly ordered, dense, and regular arrays of NWs with high uniformity and reproducibility through a simple contact printing process. We demonstrate contact printing as a versatile strategy for direct transfer and controlled positioning of various NW materials into complex structural configurations on substrates. The assembled NW pitch is shown to be readily modulated through the surface chemical treatment of the receiver substrate, with the highest density approaching ~8 NW/um, ~95% directional alignment and wafer-scale uniformity. Furthermore, we demonstrate that our printing approach enables large-scale integration of NW arrays for various device structures on both Si and plastic substrates, with a controlled semiconductor channel width, and therefore ON current, ranging from a single NW (~10 nm) and up to ~250 um, consisting of a parallel array of over 1,250 NWs.