Edward Preisler

A millimeter-wave capable SiGe BiCMOS process with 270GHz FMAX HBTs designed for high volume manufacturing

A new SiGe BiCMOS process, SBC18H3 is described which features SiGe HBTs with 240GHz FT and 270 GHz FMAX. The HBT devices are described in detail along with several other mm-wave components included in the process. The process is based on a high-volume manufacturing-proven 0.18um SiGe BiCMOS base platform which has been running at TowerJazz for almost a decade and has been used to produce over 100,000 8″ wafers. Additional mm-wave enablement devices offered in the process include MOS varactors, P-I-N diodes and sub-10fF MIM capacitors. Additional key metrics for the SiGe HBT device include an NFMIN of 2dB at 40GHz, a BVCEO of 1.6V and a DC current gain of 1200.

Demonstration of a 270 GHz f T SiGe-C HBT within a manufacturing-proven 0.18μm BiCMOS process without the use of a raised extrinsic base

SiGe bipolar transistors with FT of 270 GHz are integrated within a standard 0.18 mum CMOS process flow. These devices are built using the same architecture as Jazzpsila SBC18 SiGe BiCMOS process which has been in high-volume manufacturing for several years. The transistors have an FMAX of 170 GHz but a path to achieving an FMAX equal to FT is demonstrated without the use of selective SiGe epitaxy or raised extrinsic base poly layers. Data is shown that suggests that the target of 270 GHz FMAX can be achieved through a combination of modest design rule changes and optimization of extrinsic base doping conditions.

Integration of a 5.5V BV CEO SiGe HBT within a 200 GHz SiGe BiCMOS process flow

A novel BiCMOS integration scheme is described whereby high-performance, high breakdown-voltage SiGe HBTs can be integrated alongside ultra high performance, 200 GHz SiGe HBTs. The integration scheme is summarized and proof-of-concept data is shown to indicate the validity of the proposed scheme. It is shown that a 5.5 V BVCEO HBT with peak FT of 45 GHz can be manufactured on the same wafer as a 200 GHz HBT with zero or one additional masking layers.

Recent developments using TowerJazz SiGe BiCMOS platform for mmWave and THz applications

In this paper, we report on the highest speed 240GHz/340GHz FT/FMAX NPN which is now available for product designs in the SBC18H4 process variant of TowerJazz’s mature 0.18μm SBC18 silicon germanium (SiGe) BiCMOS technology platform. NFMIN of ~2dB at 50GHz has been obtained with these NPNs. We also describe the integration of earlier generation NPNs with FT/FMAX of 240GHz/280GHz into SBC13H3, a 0.13μm SiGe BiCMOS technology platform. Next, we detail the integration of the deep silicon via (DSV), through silicon via (TSV), high-resistivity substrate, sub-field stitching and hybrid-stitching capability into the 0.18μm SBC18 technology platform to enable higher performance and highly integrated product designs. The integration of SBC18H3 into a thick-film SOI substrate, with essentially unchanged FT and FMAX, is also described. We also report on recent circuit demonstrations using the SBC18H3 platform: (1) a 4-element phased-array 70-100GHz broadband transmit and receive chip with flat saturated power greater than 5dBm and conversion gain of 33dB; (2) a fully integrated W-band 9-element phase-controllable array with responsivity of 800MV/W and receiver NETD is 0.45K with 20ms integration time; (3) a 16-element 4x4 phased-array transmitter with scanning in both the E- and H-planes with maximum EIRP of 23-25 dBm at 100-110GHz; (4) a power efficient 200GHz VCO with -7.25dBm output power and tuning range of 3.5%; and (5) a 320GHz 16-element imaging receiver array with responsivity of 18KV/W at 315GHz, a 3dB bandwidth of 25GHz and a low NEP of 34pW/Hz1/2. Wafer-scale large-die implementation of the phased-arrays and mmWave imagers using stitching in TowerJazz SBC18 process are also discussed.

SiGe BiCMOS manufacturing platform for mmWave applications

TowerJazz offers high volume manufacturable commercial SiGe BiCMOS technology platforms to address the mmWave market. In this paper, first, the SiGe BiCMOS process technology platforms such as SBC18 and SBC13 are described. These manufacturing platforms integrate 200 GHz fT/fMAX SiGe NPN with deep trench isolation into 0.18μm and 0.13μm node CMOS processes along with high density 5.6fF/μm2 stacked MIM capacitors, high value polysilicon resistors, high-Q metal resistors, lateral PNP transistors, and triple well isolation using deep n-well for mixed-signal integration, and, multiple varactors and compact high-Q inductors for RF needs. Second, design enablement tools that maximize performance and lowers costs and time to market such as scalable PSP and HICUM models, statistical and Xsigma models, reliability modeling tools, process control model tools, inductor toolbox and transmission line models are described. Finally, demonstrations in silicon for mmWave applications in the areas of optical networking, mobile broadband, phased array radar, collision avoidance radar and W-band imaging are listed.

A broadband nonlinear lumped model for silicon IMPATT diodes

A new circuit model based on time-domain characterization of Impact Ionization Avalanche Transit-Time (IMPATT) devices is proposed. The model introduces a new 3rd order low-pass filter to accurately model the delay response of carrier drift inside the drift region, thereby capturing the dispersion caused by carrier diffusion. Moreover, non-stationary effects inside avalanche region as well as the impact of avalanche length modulation on the displacement current are modeled through nonlinear avalanche capacitance.

A study of ultra-high performance SiGe HBT devices on SOI

The authors present a study of SiGe HBTs with FT>200GHz on an SOI substrate for the first time. The devices built on SOI exhibit a degradation of approximately 7 Ghz in Ft as compared with bulk devices while Fmax remains near 280 GHz. As expected, Ccs is reduced by ~ 40%. A loss of about 0.75 V in safe operating area is observed for the HBTs built on SOI, but approximately half of this can be regained by allowing the footprint to increase to the original, bulk-silicon HBT footprint by increasing the spacing from the collector to the deep trench isolation.

Integration of SiGe NPN devices with tunable collector profiles using a single mask

An alternate local collector masking scheme is demonstrated in 0.18µm SiGe BiCMOS technology. The method relies on a resist post in the emitter window to create a set of tunable breakdown devices with a single masking step. In initial experiments we have produced a continuum of devices with fT between 31 and 74GHz. The fT × BVCEO product and fMAX of these devices is comparable to those produced with traditional local collector implementation. The method could be combined with a collector-doping scalable model to provide additional design flexibility with minimal manufacturing costs. TCAD simulations are employed to study the use of high energies and tilt angle implants to partially penetrate the LC resist post over the emitter window. This alternative relaxes the lithography requirements of the LC post and supports its use with smaller emitter geometries.

0.18µm SiGe BiCMOS technology for fully-integrated front-end ICs capable of sub-300fs R on × C off switch performance

We introduce a 0.18μm SiGe BiCMOS technology that is designed for front-end IC (FEIC) integration on a single chip. This technology employs a high-resistivity substrate and offers high-performance RF switch and low-noise amplifier (LNA) devices alongside SiGe HBTs optimized for WiFi and cellular power amplifiers (PAs). An optional through-silicon via (TSV) is also available for a low-inductance ground connection. Data measured on transmission lines, NFET RF switch branches, NFET and SiGe NPN LNA devices, and SiGe NPN PA devices built in this technology is presented and discussed.

270GHz SiGe BiCMOS manufacturing process platform for mmWave applications

TowerJazz has been offering the high volume commercial SiGe BiCMOS process technology platform, SBC18, for more than a decade. In this paper, we describe the TowerJazz SBC18H3 SiGe BiCMOS process which integrates a production ready 240GHz FT / 270 GHz FMAX SiGe HBT on a 1.8V/3.3V dual gate oxide CMOS process in the SBC18 technology platform. The high-speed NPNs in SBC18H3 process have demonstrated NFMIN of ~2dB at 40GHz, a BVceo of 1.6V and a dc current gain of 1200. This state-of-the-art process also comes with P-I-N diodes with high isolation and low insertion losses, Schottky diodes capable of exceeding cut-off frequencies of 1THz, high density stacked MIM capacitors, MOS and high performance junction varactors characterized up to 50GHz, thick upper metal layers for inductors, and various resistors such as low value and high value unsilicided poly resistors, metal and nwell resistors. Applications of the SBC18H3 platform for millimeter-wave products for automotive radars, phased array radars and Wband imaging are presented.