This manuscript introduces a new technique for depositing materials at controlled depths within porous substrates. This technique uses the passivating effect produced by one ALD precursor to prevent the adsorption of a second ALD precursor. For example, a surface exposed to trimethyl aluminum is not reactive towards diethyl zinc. This effect, combined with Knudsen diffusion through the nanopores in which the reactant exposure times dictate the depth of penetration of the ALD layer, enables spatially controlled "stripe coating" within porous supports such as anodic aluminum oxide (AAO) membranes. We have used this method to deposit stripes of ZnO, TiO2, V2O 5, and Nb2O5 at specified depths in AAO membranes The stripes were visualized by cross-sectional elemental mapping of the coated AAO membranes. The factors controlling the stripe locations and widths were identified by comparing the experimental results with the results of Monte Carlo simulations. This new technique opens up potential applications in sensors, separation devices, and multi-step catalysts.