A means of identifying a subspace in the space of all deposition profile functions is developed, where the subspace spans all spatially nonuniform deposition profiles that result in uniform profiles under rotation in radial-flow chemical vapor deposition systems with planetary wafer rotation. This model-independent uniformity criterion is used to optimize film thickness uniformity in a representative CVD system; its applicability to other film deposition system design and optimization problems is discussed. (c) 2004 Elsevier Ltd. All rights reserved.