Fractional Factorial Experiment of the Spin Coat Parameters for the Development of a Flexible Grating Coupler

Optimization of spin-coat parameters of a spin-ondielectric (SOD) onto a substrate is investigated using a two level fractional factorial design of experiment. Five parameters, spin rate, spin time, number of spin coats, volume of SOD, and the softbake temperature were varied to determine the main effect on the thickness of the deposited layers as a quality check. The layer thickness was measured using the SeminconSoft Mprobe 40 system. The number of spun layers, spin duration, spin rate, temperature, and the interaction between number of spun layers and spin rate were found to be statistically significant. A prediction model was established for the spin-coat process.