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Flexible hybrid electronics (FHE) offers potential for fast computation and communication needed in applications such as human–machine interfaces, electronic skin, etc. FHE typically comprises devices that can vary from nano‐ to chip scale, and their integration using a common process is often challenging. Herein, a printed electronics route is presented to integrate the ultrathin chips (chip‐scale) and nanowires (NWs)‐based electronic layers (nanoscale) on the same substrate. The fabrication process is categorized into three stages: i) direct transfer printing of ultrathin chips (UTCs), ii) contact printing of nanoscale structures, and iii) metal printing using the direct ink write (DIW) method to define electrodes/interconnects. The UTC printing process is carefully optimized by studying the performance of transistors present on them. Electrical data collected from 14 transistors located on 3 different chips show negligible variation in performance after they are transfer printed—thus confirming the efficacy of the printing technique. The superior grade quality of ZnO‐NWs‐based electronic layers printed on the same substrate is also demonstrated by constructing UV photodetectors using DIW printing. The photodetectors show high responsivity (≈2 × 107 A W−1) and specific detectivity (≈5 × 1015 Jones) at a low UV intensity of 0.5 µW cm−2. [ABSTRACT FROM AUTHOR]

"Heterogeneous Integration" is a promising approach for high‐performance hybrid flexible electronics that combine printed electronics and silicon technology. Despite significant progresses made by integrating rigid silicon chips on flexible substrates, the integration of flexible ultra‐thin chips (UTCs) on flexible foils remains a challenge as they are too fragile for conventional bonding methods. Reliable interconnects (low‐resistivity and mechanical robustness) and bonding of UTCs are critical to the realization of hybrid flexible systems. Herein, using a non‐contact printing approach, an easy and cost‐effective method for accessing UTCs on flexible foils is demonstrated. The high‐viscosity conductive paste, extruded from a high‐resolution printer (1–10 µm line width), is used here to connect the metal oxide semiconductor field effect transistors (MOSFETs) on UTCs with the extended pads on flexible printed circuit boards (PCBs). The electrical characterization of MOSFETs, before and after printing the interconnects, reveals an acceptable level of variation in device mobility (change from 780 to 630 cm2 V−1s−1). This is due to the drop in effective drain bias voltage as a marginally small electrical resistance (≈30 Ω) is added by the printed interconnects. The bonded UTCs show robust device performance under bending conditions, indicating high reliability of both the chip thinning and bonding methods. [ABSTRACT FROM AUTHOR]