A review on fabrication of silicon-based microchannels with a focus on chip cooling

In the post-Moore era, the ever-increasing heat flux in integrated circuits has posed severe challenges to chip thermal management. Silicon-based microchannels exhibit unique advantages as embedded cooling structures and have become a key research direction for high-performance heat dissipation. This review provides a systematic overview of typical fabrication techniques for silicon-based microchannels, including wet etching, dry etching, laser ablation, and hybrid fabrication. The basic principles, characteristics, merits and drawbacks of these methods are summarized, with emphasis on their applications in chip thermal management. The review also discusses the development trend of hybrid fabrication, which can compensate for the limitations of standalone approaches and improve flexibility and efficiency. In addition, the important role of DRIE and the promising potential of MACE-related and laser-based hybrid methods are highlighted. Fabrication-controlled geometry and surface state are further related to heat-transfer coefficient (HTC), pressure drop, critical heat flux (CHF), junction-to-fluid and package-level thermal resistance, and temperature uniformity. Recent embedded, backside/through-chip, and direct-to-package cooling approaches for AI and high-performance computing are incorporated to connect manufacturing choices with practical thermal-management requirements. This work aims to offer a clear understanding of available fabrication routes and provide guidance for the design and development of efficient microchannel cooling devices.