A system includes a memory, and at least one processing device, operatively coupled to the memory, to facilitate an etch recipe development process by performing operations including obtaining, from an optical detector, first material thickness data for a first material and second material thickness data for a second material resulting from an iteration of an etch process using an etch recipe. The first material is located at a first reflectometry measurement point and the second material is located at a second reflectometry measurement point different from the first reflectometry measurement point. The operations further include determining one or more etch parameters based on at least the first material thickness data and the second material thickness data.