Related Experiment Video
Updated: Feb 26, 2026
08:07
Ultrahigh Density Array of Vertically Aligned Small-molecular Organic Nanowires on Arbitrary Substrates
Published on: June 18, 2013
15.5K
High-Density Sub-10 nm Silicon Nanowires Fabricated via Directed Self-Assembly and Sequential Infiltration Synthesis
Gang Chen1, Hui Xie1, Jiacheng Luo2
1State Key Laboratory of Integrated Chips and Systems, College of Integrated Circuits and Micro-Nano Electronics, Fudan University, Shanghai 200438, People's Republic of China.
ACS Nano
|February 24, 2026
Summary
This study introduces a novel directed self-assembly lithography (DSA) and sequential infiltration synthesis (SIS) technique to create high-density silicon nanowires. This method enables advanced applications in ultrasensitive gas sensing and high-performance FinFET transistors.
Area of Science:
- Materials Science and Nanotechnology
- Semiconductor Device Fabrication
- Lithography Techniques
Background:
- Fabricating high-density, small-dimension silicon nanowires is crucial for advanced electronics and sensors.
- Existing methods often involve complex, multi-step processes with limited scalability.
- Directed self-assembly lithography (DSA) and sequential infiltration synthesis (SIS) offer potential for precise nanostructure fabrication.
Purpose of the Study:
- To develop a synergistic patterning technique integrating DSA and SIS for fabricating high-density silicon nanowires on silicon-on-insulator (SOI) substrates.
- To optimize the process for creating nanowires with small critical dimensions and high aspect ratios.
- To demonstrate the application of these fabricated nanowires in gas sensing and FinFET devices.
Main Methods:
- Integration of directed self-assembly lithography (DSA) with sequential infiltration synthesis (SIS) on SOI substrates.
- Optimization of polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) guiding templates and SIS cycles.
- In situ conversion of polymer templates into aluminum oxide (Al2O3) hard masks and utilization of a silicon dioxide (SiO2) intermediate mask strategy.
Main Results:
- Fabrication of silicon nanowires with a top width of ~6.6 nm, bottom width of ~14.9 nm, pitch of 28 nm, and height of ~53.5 nm.
- Demonstration of ultrasensitive ammonia (NH3) gas sensing with a 49.8% response to 2.5 ppm.
- Development of FinFET devices with a switching ratio >10^7 and subthreshold swing as low as 69.59 mV/dec.
Conclusions:
- The synergistic DSA-SIS technique provides a cost-effective method for manufacturing high-density silicon nanowires.
- The fabricated sub-10 nm silicon nanowires exhibit excellent gas-sensing performance.
- DSA-SIS technology shows significant potential for fabricating nanostructures for both sensing and integrated circuit applications.
