High-speed NMOS depletion-load ring oscillators and dynamic shift registers have been fabricated from laser-crystallized silicon thin-film transistors (TFT's) on fused quartz. We report on optimization of circuit fabrication process involving ion implantation and high temperature cycles to achieve inverter gains, logic thresholds, and input noise margins appropriate for logic operation. Characteristics of discrete devices are also used to evaluate a process simulator and a device simulator as tools for future designs.