Self‐Rolled‐Up Ultrathin Single‐Crystalline Silicon Nanomembranes for On‐Chip Tubular Polarization Photodetectors

Abstract

Freestanding single‐crystalline nanomembranes and their assembly have broad application potential in photodetectors for integrated chips. However, the release and self‐assembly process of single‐crystalline semiconductor nanomembranes still remains great challenges in on‐chip processing and functional integration, and photodetectors based on nanomembrane always suffer from limited absorption of nanoscale thickness. Here, we employ a non‐destructive releasing and rolling process to prepare tubular photodetectors based on freestanding single‐crystalline Si nanomembranes. Spontaneous release and self‐assembly are achieved by residual strain introduced by lattice mismatch at the epitaxial interface of Si and Ge, and the intrinsic stress and strain distributions in self‐rolled‐up Si nanomembranes are analyzed experimentally and computationally. The advantages of light trapping and wide‐angle optical coupling are realized by tubular geometry. Our Si microtube device achieves reliable Ohmic contact and exhibits a photoresponsivity of over 330 mA/W, a response time of 370 μs, and a light incident detection angle range of over 120°. Furthermore, the microtubular structure shows a distinct polarization angle‐dependent light absorption, with a dichroic ratio of 1.24 achieved at 940 nm. The proposed Si‐based microtubes provide new possibilities for the construction of multifunctional chips for integrated circuit ecosystems in More than Moore era.This article is protected by copyright. All rights reserved

Multilevel design and construction in nanomembrane rolling for three-dimensional angle-sensitive photodetection

“…6f , the ring (Fig. 6g ) and tube photodetectors exhibit a wider detection angle of high photocurrent 8 , 23 , confirming that the 3D microstructure contributes to the anisotropic detection of incident light and enhancing the detection of φ in area of θ = 70°–110°. For the arch photodetector (Fig.…”

“…Three-dimensional (3D) structure assembled by releasing pre-strain nanomembrane has become an essential technique for electronic 1 – 4 , optical 5 – 8 , and magnetic 9 – 11 applications. The self-assembly of the nanomembrane depends on the large deformation in ultrathin thickness and the out-plane strain gradient in a multilayer nanomembrane system.…”

“…Generally, the strain gradient derives from thermal strain that is caused by temperature change, recovery of pre-stretched substrate, and lattice mismatch of epitaxial material. By tuning etching edges, nanomembrane systems, and deposition parameters, preparation of tubes 12 – 14 , helices 15 – 17 , buckles 18 , 19 , and other structures 20 – 22 have been achieved for applications in photodetectors 8 , 23 , field effect transistors 24 , 25 , and microrobots 13 , 26 . However, the formation of nanomembrane is affected by multiple complex factors in the release process, such as etching trajectory, balance between chemical reaction and etchant diffusion, fluid behaviors of etchant, aspect ratio, etc.…”

Demonstration of a 3D-Assembled Dual-Mode Photodetector Based on Tubular Graphene/III–V Semiconductors Heterostructure and Coplanar Three Electrodes

“…17−19 Now, transforming specific planar 2D structures into tubular 3D structures has become one satisfied solution, by which several attractive features (e.g., light trapping effect, omnidirectional ability, and high spatial resolution) can be introduced into photodetectors and subsequently endows the photodetectors high performance and multifunction. 20,21 Lu et al have facilitated rolled-up tubular GaAs quantum well infrared photodetector and have shown the omnidirectional photodetection capability, such a device also holds high- performance photodetection which is enabled by the tubesupported light-trapping mode, and its responsivity of ∼30 mA/W under 0.65 V bias voltage at 60 K low-temperature was shown. 22 Inspired by the excellent characteristic of 2D materials such as ultrahigh electron mobility, 23 wide-spectrum optical absorption, 24 and adjustable band gap, 25 rolled-up tubular 2D material photodetectors have also been fabricated and enriched the family of 2D materials-based photodetectors.…”

“…Photodetectors can convert optical signals into electrical signals − and have great values in optical communications, − image sensing, − remote sensing, , and many other application fields. − Regrettably, the widely adopted planar photodetectors usually have poor response to the tilted incident light, making it quite difficult to fulfill the wide-angle photodetection mission . Along with the development of three-dimensional (3D) assembly technology, especially the self-rolled-up technology, solving such long-stand obstacle has ushered in a critical turning point. − Now, transforming specific planar 2D structures into tubular 3D structures has become one satisfied solution, by which several attractive features (e.g., light trapping effect, omnidirectional ability, and high spatial resolution) can be introduced into photodetectors and subsequently endows the photodetectors high performance and multifunction. , …”