Process Design and Thermal Simulations of a Single Layer Microbolometer

In this study, design of a single layer microbolometer detector pixel together with its fabrication process design and thermal simulations are presented. A four-step process is designed and proposed for the fabrication of single layer microbolometer detectors. During the study, the single layer, which will be used as the structural and the absorber layer, is chosen as zinc-oxide (ZnO), since it previously was shown that ZnO can be used as single layer microbolometer detector material. Different types of pixels are designed and simulated. From the results of the simulations, the thermal conductance and the thermal time constant values of the pixels are obtained. When the results are compared, the pixel with 0.5 μm arm and gap width has the lowest thermal conductance value of 5x10-7 W/K, and its thermal time constant value is simulated as 2.8 ms which is compatible with the requirements for the infrared imaging systems operating at 30 fps.