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Vol. 18 (2026)

Wafer-Level Self-Assembly and Interface Passivation Patterning Technology for Nanomaterial-Compatible 3D MEMS Sensing Chips

https://doi.org/10.1007/s40820-026-02080-4
Zheng Zhang
School of Integrated Circuits, Huazhong University of Science and Technology, Wuhan 430074, People’s Republic of China
Yanlin Zhang
School of Integrated Circuits, Huazhong University of Science and Technology, Wuhan 430074, People’s Republic of China
Yuanyuan Luo
Key Laboratory of Materials Physics, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, People’s Republic of China
Guoliang Lv
School of Integrated Circuits, Huazhong University of Science and Technology, Wuhan 430074, People’s Republic of China
Jianglin Yin
School of Integrated Circuits, Huazhong University of Science and Technology, Wuhan 430074, People’s Republic of China
Pengwei Tan
School of Integrated Circuits, Huazhong University of Science and Technology, Wuhan 430074, People’s Republic of China
Guotao Duan
School of Integrated Circuits, Huazhong University of Science and Technology, Wuhan 430074, People’s Republic of China

Corresponding Author: Guotao Duan

duangt@hust.edu.cn

Nano-Micro Letters, Vol. 18 (2026), Article Number: 221

Abstract

Wafer-scale fabrication of high-performance micro-electro-mechanical systems (MEMS) bio/chemical sensing chips remains constrained by the absence of reliable methods for integrating high-performance nanomaterials into suspended MEMS architectures. Here, a wafer-level manufacturing strategy is presented that redefines the MEMS process flow as “film first, cantilever later.” Through kinetically controlled self-assembly, wet-chemically synthesized Pd/SnO2 nanospheres are transferred as dense, uniform monolithic films onto 8-inch wafers. An HfO2 interface passivation patterning technology resolves long-standing incompatibility between functional sensing films and silicon substrates, enabling precise patterning and reliable integration on suspended MEMS cantilevers. The resulting Pd/SnO2 MEMS H2 chips are fabricated onto an 8-inch wafer, demonstrating high sensitivity and consistency. This approach overcomes long-standing wafer-level manufacturing challenges in the formation and patterning of high-performance nanomaterials film, establishing a fully integrated wafer-level process that fundamentally redefines the manufacturing route for tetramethylammonium hydroxide-resistant nanomaterial-based MEMS sensing chips.


Highlights:
1 Wafer-scale, kinetically controlled self-assembly combined with edge-controlled lift-off enables uniform and precisely patterned nanomaterial films on 8-inch wafers.
2 HfO2 interface passivation eliminates wet etching failures and ensures reliable integration with suspended microelectro-mechanical systems (MEMS) structures.
3 A“film-first, cantilever-later” strategy realizes 3D MEMS gas sensing chips with accurate nanomaterial incorporation, delivering high H2 sensitivity and uniformity.

Keywords

Compatible manufacturing Wafer-level self-assembly Interface passivation patterning technology MEMS Sensing chips
Zhang, Zheng, Yanlin Zhang, Yuanyuan Luo, Guoliang Lv, Jianglin Yin, Pengwei Tan, and Guotao Duan. 2026. “Wafer-Level Self-Assembly and Interface Passivation Patterning Technology for Nanomaterial-Compatible 3D MEMS Sensing Chips”. Nano-Micro Letters 18 (January):221. https://doi.org/10.1007/s40820-026-02080-4.
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