Stacked Heterostructure Barrier Varactors on InP for Millimeter Wave Triplers

Single-barrier varactors reported earlier were limited in their power output. By using a pseudomorphic In
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Al
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As/AlAs/In
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Al
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As barrier with good current blocking characteristics and stacking three varactor layers by MBE technique, we report the first symmetric stacked varactor on InP with low leakage, high breakdown voltage (≈ 14V) and 50 mW power output capability at 39 GHz, 20 mW at 186 GHz.