Apparatus and method of processing a substrate according to a PECVD process is described. Temperature profile of the substrate is adjusted to change deposition rate profile across the substrate. Plasma density profile is adjusted to change deposition rate profile across the substrate. Chamber surfaces exposed to the plasma are heated to improve plasma density uniformity and reduce formation of low quality deposits on chamber surfaces. In situ metrology may be used to monitor progress of a deposition process and trigger control actions involving substrate temperature profile, plasma density profile, pressure, temperature, and flow of reactants.