the last one thx you so so so much
by two orders of magnitude.Unfortunately,the poor resistivity of the silicon substrate does not allow the use of very high frequencies.Use of a high resistivity GaAs substrate with a much lower rf loss will make higher microwave fre- quencies feasible with a corresponding increase in sensitiv- ity.We note that oscillators and mixers can be realized up to several GHz on silicon substrates and several tens of GHz on GaAs substrates.It should be possible to fabricate a large array of sensitive detectors monolithically integrated with their associated electronics.