A method of modifying a substrate carrier to improve process performance includes depositing material or fabricating devices on a substrate supported by a substrate carrier. A parameter of layers deposited on the substrate is then measured as a function of their corresponding positions on the substrate carrier. The measured parameter of at least some devices fabricated on the substrate or a property of the deposited layers is related to a physical characteristic of substrate carrier to obtain a plurality of physical characteristics of the substrate carrier corresponding to a plurality of positions on the substrate carrier. The physical characteristic of the substrate carrier is then modified at one or more of the plurality of corresponding positions on the substrate carrier to obtain desired parameters of the deposited layers or fabricated devices as a function of position on the substrate carrier.