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Intrinsic silicon (Si) is forbidden for infrared (IR) sensing at the communication wavelength like 1.31 or 1.55 µm due to the well‐known bandgap limitation. In this work, an unexpected physical picture of using argon (Ar) is identified, which is usually inert to the surrounding chemical environment and used as a protective agent in semiconductor processing, to overcome the IR‐sensing‐forbidden problem in Si. Here, it is shown by an analysis of a dynamic secondary ion mass spectrometer that such a Si, when exposed to laser pulse in Ar gas, can contain a very high dose of Ar up to 1020 cm−3 even after 1300 days. First‐principles calculations, molecular dynamics, and Hall effect measurements reveal that, due to both steric and dynamic repulsions by Ar orbitals to Si dangling bonds, the Ar‐filled‐vacancy produces a much wider defect band inside the gap, which is not only responsible for strong infrared absorption, but also causes a significant increase in n‐type conductivity, both in line with experiments. The study proves that originally inert elements in fact can act as active impurities in semiconductors for advanced applications, which updates the current knowledge of defect physics. [ABSTRACT FROM AUTHOR]

Colloidal quantum dots (QDs) have been widely studied in display panels due to their near‐unity fluorescence quantum yield and the ability to tune colors across a wide gamut. However, the challenge persists in creating full‐color QD arrays with the necessary precision for high‐resolution display applications in the next generation. This paper introduces a femtosecond laser‐induced forward transfer (FsLIFT) technology that integrates deposition pattern and alignment in a single transfer step. This development enables the fabrication of high‐resolution full‐color QD films. The ability of FsLIFT to precisely locate red, green, and blue QDs in a designated position allows to obtain arbitrarily shaped full‐color patterns and pixel arrays with a resolution of 1.78 µm. In addition, the potential for optoelectronic devices is ensured by the preserved photophysical properties, high smoothness, and continuity of the transferred QD films. Consequently, the light‐emitting diodes (LEDs) are successfully fabricated based on the transferred QD films. This study expects that the introduced straightforward patterning technology, offering high freedom, precision, and repeatability, will contribute to advancing the development of full‐color high‐resolution displays based on QDs. [ABSTRACT FROM AUTHOR]