Tomas Kraemer

InP DHBT Process in Transferred-Substrate Technology With

In this paper, a double heterojunction bipolar transistor (DHBT) process has been developed in transferred-substrate (TS) technology to optimize high-frequency performance. It provides an aligned lithographic access to frontside and backside of the device to eliminate dominant transistor parasitics. The transistors of 0.8 times 5-mum2 emitter mesa feature ft = 410 GHz and fmax = 480 GHz at a BVceo = 5.5 V. Parallel to the device setup, a multilevel metallization scheme is established. It serves as construction kit for 3-D configurations of active and passive elements. High yield of the TS DHBTs, consistent large-signal modeling, and accurate simulation of complex passive elements have been demonstrated and have proved the availability of the technology for advanced millimeter-wave circuit design.

f_{t}

This paper presents a novel InP-SiGe BiCMOS technology using wafer-scale heterogeneous integration. The vertical stacking of the InP double heterojunction bipolar transistor (DHBT) circuitry directly on top of the BiCMOS wafer enables ultra-broadband interconnects with <; 0.2 dB insertion loss from 0-100 GHz. The 0.8 × 5 μm2 InP DHBTs show fT/fmax of 400/350 GHz with an output power of more than 26 mW at 96 GHz. These are record values for a heterogeneously integrated transistor on silicon. As a circuit example, a 164-GHz signal source is presented. It features a voltage-controlled oscillator in BiCMOS, which drives a doubler-amplifier chain in InP DHBT technology.

and

A 246 GHz source in InP-on-BiCMOS technology is presented. It consists of a voltage controlled oscillator (VCO) in BiCMOS technology and a frequency tripler in transferred-substrate InP-HBT technology, which is integrated on top of the BiCMOS MMIC in a wafer-level bonding process. The VCO operates at 82 GHz with 6 dBm output power and the combined circuit delivers -10 dBm at 246 GHz, with a phase noise of -87 dBc/Hz at 2 MHz offset. To the knowledge of the authors, this is the first hetero-integrated signal source in this frequency range reported so far. The results illustrate the potential of the hetero integrated process for sub-mm-wave frequencies.

f_{\max}

In order to combine the advantages of both InP-HBT and SiGe-BiCMOS technology, a 3D integration approach has been developed based on the transferred-substrate concept with BCB wafer bonding. Using this process vertical interconnects are realized that exhibit excellent broadband transmission properties up to 220 GHz. Insertion loss remains below 0.5dB up to W-band and 1dB to 220GHz. The interconnects can be described with good accuracy by 3D EM simulation over the full frequency range.

Over 400 GHz

In this paper, the small- and large-signal modeling of InP heterojunction bipolar transistors (HBTs) in transferred substrate (TS) technology is investigated. The small-signal equivalent circuit parameters for TS-HBTs in two-terminal and three-terminal configurations are determined by employing a direct parameter extraction methodology dedicated to III–V based HBTs. It is shown that the modeling of measured S-parameters can be improved in the millimeter-wave frequency range by augmenting the small-signal model with a description of AC current crowding. The extracted elements of the small-signal model structure are employed as a starting point for the extraction of a large-signal model. The developed large-signal model for the TS-HBTs accurately predicts the DC over temperature and small-signal performance over bias as well as the large-signal performance at millimeter-wave frequencies.

InP-DHBT-on-BiCMOS Technology With

A 197-GHz fixed-frequency fundamental oscillator with high efficiency is presented, realized using a transferred-substrate InP-DHBT process. It delivers 0 dBm output power, with a phase noise of -88 dBc/Hz at 1.6 MHz offset frequency. DC consumption is only 22 mW from a 1.4 volts power supply, which corresponds to the highest overall DC-to-RF efficiency of a millimeter-wave frequency source reported to date.