Oxide semiconductor-based neuromorphic devices hold great potential for visual information processing, yet their performance is critically limited by photolithography-induced organic residues. This work systematically investigates the effects of photoresist contaminants on In-Ga-Zn-O thin-film transistors (IGZO TFTs), revealing that these residues introduce deep-level trap states that degrade both photo-responsivity and carrier transport dynamics. Through optimized plasma-assisted surface treatments, these adverse effects would be effectively eliminated. Additionally, we show that gate-voltage modulation can precisely control the relaxation kinetics of photocarriers in these devices. By applying these strategies to IGZO-based synaptic arrays, we achieve enhanced image contrast through controlled optoelectronic response modulation. Overall, our findings highlight the critical impact of photolithography-induced organic residues in IGZO optoelectronic synaptic devices and demonstrate an effective approach for performance enhancement through surface plasma treatment and gate-voltage modulation.

A high-speed single-mode vertical-cavity surface-emitting laser (VCSEL) is one of the most important light sources for optical interconnects in data centers. Single-mode VCSEL can improve the transmission distance. In this letter, we demonstrate a single-mode 850nm VCSEL with a bit rate of 60 Gb/s under NRZ modulation and 104 Gb/s under PAM4 modulation across a 100 m length of OM5 fiber, without the need for equalization or a filter. In addition, by using optical injection locking, the 3dB bandwidth is enhanced to 68.5 GHz.