4.6 �m PLATING CAP TOP PLATE 2000 � NITRIDE 0.75 �m FIRST METAL TaN RESISTOR T-GATE ACTIVE REGION OHMIC METAL (EXCEPT VIA) SEMI-INSULATING GaAs SUBSTRATEFeatures
0.25-�m amplifier transistors 0.25-�m switch transistors 0.25-�m diodes Device passivation High-Q passives MIM capacitors TaN resistors GaAs resistors 2 metal layers Air bridges Substrate vias Operation to 20 GHz Communications Space Military Power amplifiers Driver amplifiers Low-noise amplifiers AGC amplifiers Limiting amplifiers Transimpedance amplifiers Differential amplifiers Digital and analog phase shifters Digital and analog attenuators Mixers (up and down converters) Switches OscillatorsApplications
The 0.25-�m Ku pHEMT 2MI (2-metal-interconnect) process utilizes T-gate depletion-mode transistors and is optimized for high power applications through 20 GHz. The process demonstrates comparable power density and gain to the 0.25-�m mmW pHEMT 2MI process at X-band frequencies and similar bias conditions. However, the 0.25�m Ku pHEMT offers a higher breakdown voltage allowing higher bias voltages to be applied to deliver higher power densities. Passives include 2 thick-metal interconnect layers, precision TaN resistors, GaAs resistors, MIM capacitors and through-substrate vias. The via-under-cap process aids in size compaction and offers excellent grounds at higher frequencies. Air bridges produce minimal interconnect capacitance. This process is suitable for commercial, military and space applications.
0.25-�m Ku pHEMT 2MI Process Details Element Parameter Typical Value Units FETs Idss 285 mA/mm Imax Gm Vbd Vp Ft (peak) MIM capacitors Capacitors over vias TaN resistors GaAs resistors Vias Substrate density sheet resistance sheet resistance thickness yes 50 160 yes 100 mA/mm mS/mm V GHz pF/mm V/sq �m0.25-�m Ku pHEMT 2MI Maximum Available Gain/Stable Gain (MAG/MSG) 800-�m FET @ 3 Volts, 60 mA