Enhancing the resilience of the complex semiconductor value chain requires better data. This paper strengthens the evidence base for semiconductor policy by mapping global semiconductor wafer fabrication capacity by economy, process node density, process technology and business model, building on the newly assembled OECD Semiconductor Production Database. The results show that semiconductor production capacity is highly geographically concentrated and underscore the importance of distinguishing between different semiconductor types and the limited scope for substitutability of production between fabrication plants. This structural rigidity creates bottlenecks that can amplify the impact of supply disruptions and limit the scope for remedial actions. Enhancing the resilience of the global semiconductor value chain will require further co-operation among like-minded economies, developing better data and exploring opportunities for greater diversification to reduce systemic risks.