Abstract: An active balun amplifier includes a first plurality of metal oxide semiconductor (MOS) transistors arranged in series, the first plurality of MOS transistors comprising a first input transistor of a first conductivity type, a second input transistor of a second conductivity type, and at least two common-gate transistors arranged in series between the first input transistor and the second input transistor, wherein a gate of the first input transistor and a gate of the second input transistor are tied to a common input, a second plurality of MOS transistors arranged in series, the second plurality of MOS transistors comprising a first common-source transistor of the first conductivity type, a second common-source transistor of the second conductivity type, and at least two cascode transistors arranged in series between the first common-source transistor and the second common-source transistor.

Abstract: A method of forming a semiconductor device includes etching a semiconductor layer to form a plurality of mesa stripes in the semiconductor layer. The plurality of mesa stripes extend in a first direction and include mesa sidewalls that extend in the first direction and mesa surfaces at opposite ends of the mesa stripes. An additional mesa region is formed at an end of at least one of the mesa stripes. The additional mesa region is electrically insulated from the at least one of the mesa stripes. A semiconductor device structure includes a plurality of mesa stripes that extend in a first direction and include mesa sidewalls that extend in the first direction and mesa end surfaces at opposite ends of the mesa stripes. An additional mesa region that is electrically insulated from the at least one of the mesa stripes is at an end of at least one of the mesa stripes.