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Page 6 of 29 Wang et al. Soft Sci. 2025, 5, 28 https://dx.doi.org/10.20517/ss.2025.11

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lithography , as shown in Figure 3A. This symmetrical electrode structure ensures uniform signal
acquisition, minimizes noise interference, and enhances both sensitivity and stability, making it suitable for
scenarios with uniformly distributed pressure. Wang et al. developed stretchable electronic devices
[73]
interconnected by liquid metal and conductive nanocomposite materials . The independent sensing units
effectively eliminate crosstalk between individual units. Furthermore, Lin et al. adopted a cross-laminated
[74]
electrode arrangement, organizing the sensing units into a cross-array configuration . This approach
improves spatial utilization, enables high-density sensing, and reduces interference between adjacent
electrodes, rendering it ideal for large-area, high-precision tactile sensing applications. Other studies have
incorporated microstructures into the compositional layers of sensors. Shi et al. proposed a machine tactile
sensing system based on micropillars. The system can successfully measure three-dimensional (3D) force
and temperature distribution simultaneously . Park et al. developed a sensor array with a micro-dome
[75]
interlocking structure . The dome-shaped microstructure design enhances the linearity and sensitivity of
[76]
signal output, improving the resolution of the tactile sensor. Wang et al. made a piezoresistive sensor array
(PRSA) with a micro-pyramid-structured pressure-sensitive layer to boost sensitivity . This design allows
[77]
the top layer to better detect mechanical contacts, thus improving the sensor array’s sensitivity. In recent
years, many research works have innovatively designed arrays based on bionic structures, such as cilia-based
e-skin and fingerprint microstructures , inspired by biological skin and neural networks. Yan et al.
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successfully fabricated a bioinspired cilia-based e-skin that enables the sensing and detection of surface
[79]
morphology, Braille, and airflow velocity , as shown in Figure 3E. The bioinspired cilia exhibited a linear
sensing range for static detection, with bending angles from 15° to 60°, and a frequency range of 1-25 Hz for
dynamic sensing. These designs enhance the sensor’s comprehensive perception of various external stimuli
(e.g., pressure, strain), making them more suitable for intelligent health monitoring and human-computer
interaction. The combination of these structural design strategies enables flexible sensor arrays to meet
diverse needs, including high precision and stretchability, and propels the development of intelligent
sensing technology.

Manufacturing methods
With the development of information technology and new material science, innovations in manufacturing
techniques have significantly contributed to the advancement of flexible sensor arrays. Common methods
include coating, templating, laser processing, and nanoimprinting. Quan et al. fabricated a flexible
capacitive micro-structured sensor with a sandwich structure, using spraying to deposit AgNWs on PDMS
[80]
film . Shuai et al. prepared a capacitive pressure sensor with elastic electrodes and microarray structures,
using filtration and spin-coating to cover AgNWs on PVDF film as the dielectric layer . Coating is widely
[81]
used for preparing conductive layers of sensor arrays due to its ability to rapidly deposit conductive
materials . Gao et al. prepared a degradable chitosan (CS) polymer triboelectric layer using templating and
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plasticization, enhancing power generation and sensor performance . Yang et al. used templating to
[83]
prepare micro-pyramid dielectric layers with porous structures for high sensitivity . Making templates is a
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commonly used method for preparing microstructures due to its simplicity and low cost. Laser direct
writing (LDW) has emerged as a powerful patterning technology offering high precision, high throughput,
mask-free operation and programmable flexibility . These advantages enable the efficient manufacture of a
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wide range of advanced electronic devices such as wearable strain sensors, artificial necks, heterostructure
transistors and flexible supercapacitors [86-88] . In addition, the high-precision capabilities of LDW have
extended its applications to include the fabrication of flexible pressure sensor arrays, making it an
indispensable tool for modern electronics manufacturing. Kim et al. used femtosecond laser technology to
create patterned micro/nanostructures on PDMS, increasing contact areas between metal electrodes and
[89]
polymer triboelectric layers and improving triboelectric nanogenerator (TENG) device power density .
Yan et al. developed a flexible high-resolution triboelectric sensing array (TSA) for self-powered real-time
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tactile sensing through LDW . The process of fabrication is shown in Figure 4C. Nanoimprinting