Test structures for the evaluation of air-bridge interconnection in GaAs IC´s fabrication process

Specially designed test structures have been developed for the first time in order to evaluate the deflection of the air-bridge which is an indispensable structure for improving the device performance by reducing stray capacitances. It is found that the origin of the deflection strongly depends on the layout of the interconnection pattern under the air-bridge and air-bridge dimensions. By using, newly developed test structures, we can easily optimize the air-bridge design and process parameters to obtain high performance GaAs IC devices and to shrink the chip size while maintaining high reliability