The results are presented of a theoretical study on the yield stress of dislocation‐lean silicon. The obtained yield formula, which expresses the dependence of the external yield force on the intrinsic point defect concentration, is applied to the case of film edge induced dislocation generation in silicon substrates. A generally valid expression for the critical film thickness resulting in homogeneous defect nucleation is derived. The case of an inert anneal of dislocation‐lean, oxygen‐rich Czochralski silicon is studied more in detail. The theoretical results explain both the qualitative and the quantitative experimental results found in the literature.