Laser-Patterned Nitrogen-Doped Silicon Carbide For Organ-On-Chip And Bioelectric Applications
SUMMARY
A laser-writing process converts selected regions of PDMS into nitrogen-doped cubic silicon carbide with an integrated graphite layer, producing flexible semiconductor biointerfaces that can be patterned in 2D or formed into freestanding 3D structures.
The Unmet Need: Scalable, flexible biointerfaces that combine soft-substrate compatibility with active electrical or photoelectrochemical function without relying on costly conventional semiconductor fabrication
- Soft biointerfaces are increasingly important in organ-on-chip systems, preclinical tissue models, and next-generation bioelectronic devices. Many current interfaces rely on metal electrodes or traditional semiconductor fabrication methods that can be expensive, rigid, or difficult to integrate into soft polymer systems. PDMS is widely used in biological research and microfluidics because of its flexibility, optical compatibility, and ease of handling, but it is electrically insulating. Converting part of a PDMS structure into an active semiconductor or conductor would enable new device architectures with fewer assembly steps. Silicon carbide is attractive because of its chemical stability and favorable electronic properties, including the performance of cubic 3C-SiC. However, conventional synthesis of 3C-SiC can require stringent processing conditions.
The Proposed Solution: A direct laser-fabrication method for creating nitrogen-doped 3C-SiC/graphite structures inside PDMS, enabling flexible biointerfaces for electrical and photoelectrochemical modulation
- The faculty inventor developed a new way to build active biointerfaces directly inside soft polymer devices. Rather than attaching rigid semiconductors or depositing multiple separate conductive layers, a laser converts selected regions of PDMS into nitrogen-doped 3C-SiC while also generating an underlying graphite network for electrical connection. The resulting composite can be patterned into flexible electrodes, photoactive regions, and 3D structures that support electrical stimulation, localized peroxide generation, and other biologically relevant signaling functions. This approach has the potential to simplify manufacturing, reduce integration complexity, and enable new classes of organ-on-chip, microfluidic, and soft bioelectronic devices.
FIGURE
(A) CO2 laser writing a pattern on a PDMS substrate wherein the pattern can be (i) on the surface, (ii) a trench, or (iii) a cut-through leading to the formation of two distinct pieces. Architectures (i) to (iii) arise as a function of the laser power and writing speed. A graphite layer forms beneath the SiC because of the nature of the ablation process. (B) Laser-written electrodes are flexible electrodes that can integrate with a heart and stimulate it with electrical impulses leading to its pacing. (C) Laser-written circuits can be used for photoelectrochemical modulation of interconnected cellular ensembles.
ADVANTAGES
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Rapid and potentially lower-cost fabrication
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Compatible with soft-material device architectures
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Multifunctional platform rather than single-mode electrode
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Attractive for organ-on-chip, assay, and bioelectronic applications
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May simplify prototyping versus traditional semiconductor processing
APPLICATIONS
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Flexible electrodes for pacing isolated hearts
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Photoelectrodes for local modulation of smooth muscle sheets through peroxide generation
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Potential use in research biointerfaces and integrated stimulation devices
PUBLICATIONS