Integrating environmental and resilience metrics for sustainable material substitution in compound semiconductor laser manufacturing

Compound semiconductor manufacturing faces growing challenges from critical raw material dependence and environmental burdens. This study develops a physics-informed multi-criteria life cycle framework integrating environmental and resilience metrics to evaluate sustainable material substitution. The framework combines life cycle assessment (LCA), material circularity indicators (MCI), and a supply risk index (SRI) within a multi-criteria decision analysis (MCDA) structure. The approach is demonstrated through a ‘case study’ comparing gallium arsenide (GaAs) and germanium (Ge) substrates in vertical-cavity surface-emitting laser (VCSEL) production. Results show that Ge exhibits 11.4% lower cumulative energy demand, a 0.54 vs. 0.33 MCI, and a 0.18 vs. 0.39 SRI, resulting in a 4.2-fold higher composite sustainability score (0.822 vs. 0.194). These advantages are driven by Ge’s diversified supply base, higher recyclability, and absence of arsenic-related toxicity. Although GaAs currently benefits from greater process maturity, its environmental and geopolitical vulnerabilities highlight the long-term advantages of Ge substitution, while also indicating trade-offs in terms of short-term economic implications related to yield, process maturity, and manufacturing transition. The proposed framework offers a transferable decision-support tool for integrating environmental sustainability and supply-chain resilience into material selection and manufacturing strategies for advanced-technology industries.