A 150 GHz Amplifier With 8 dB Gain and $+$6 dBm $P_{\rm sat}$ in Digital 65 nm CMOS Using Dummy-Prefilled Microstrip Lines

Abstract

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A 150 GHz amplifier in digital 65 nm CMOS process is presented. Matching loss is reduced and bandwidth extended by simplistic topology: no dc-block capacitor, shunt-only tuning and radial stubs for ac ground. Dummy-prefilled microstrip lines, with explicit yet efficient dummy modeling, are used as a compact, density-rule compliant matching element. Transistor layout with parallel gate feed yields 5.7 dB of MSG at 150 GHz. Measurement shows the amplifier exhibits 8.2 dB of gain, 6.3 dBm of <formula formulatype="inline"> <tex Notation="TeX">$P_{\rm sat}$</tex></formula>, 1.5<formula formulatype="inline"> <tex Notation="TeX">$~$</tex></formula>dBm of <formula formulatype="inline"> <tex Notation="TeX">$P_{\rm 1dB}$</tex></formula> and 27 GHz of 3 dB bandwidth, while consuming 25.5 mW at 1.1 V. The dummy-prefilled microstrip line exhibits <formula formulatype="inline"><tex Notation="TeX">$Q_{TL}\cong 12$</tex></formula> up to 200 GHz. </para>