With the rapid development of healthcare and human‐machine interactions, there is a growing demand for flexible electronic skin to have a high sensitivity over a wide range. While current multilevel and hierarchical structures inspired by nature broadened the sensing range, the structural design still lacks systematic study. Hereby, an ordered multilevel microstructure is proposed, and the design strategy for performance regulation of piezoresistive pressure sensors is studied. Both microstructure height and spatial distribution are investigated systematically through simulation and experiments. The flexible piezoresistive pressure sensor is fabricated by combining a fast, cost‐effective laser marking technology, molding, and pneumatic spray. The fabricated sensors show high sensitivity (1.5 – 8.3 kPa−1) over a wide range (0.01 – 200 kPa), and have a detection limit of 10 Pa, a response time of below 70 ms, and a mechanical stability over 10 000 cycles. This design and fabrication strategy can be further optimized by combining advanced materials and fabrication systems, and is expected to be applicable for a wide range of flexible materials.

With the development of micro‐nano manufacturing technology, various hierarchical microstructures (HMs) are used to improve the sensitivity and measurement range of flexible pressure sensors. However, the fabrication of highly ordered HMs in simple, fast, and low‐cost ways remains a great challenge. In this work, laser direct writing technology is used to fabricate highly ordered HMs to enhance the sensitivity of flexible piezoresistive sensors. The HMs show a lateral expansion with the increasing pressure due to good flexibility and small force bearing areas, resulting in more significant change in contact area than the single‐level microstructures, which leads to an enhanced sensitivity. Two case studies are conducted to verify the performance of the sensor with laser processed HMs. Experimental results show that the pulsating blood pressure signal of radial artery can be detected by attaching the sensor on the wrist. When the sensor is attached on the neck, it can also detect the vibration signal of vocal cord when speaking. These results successfully demonstrate the potential of laser processing in fabricating highly ordered HMs to achieve highly sensitive flexible piezoresistive sensors for various applications, such as wearable health monitoring and human–computer interactions.

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