Kenneth J. Stein

Self-aligned SiGe NPN transistors with 285 GHz f/sub MAX/ and 207 GHz f/sub T/ in a manufacturable technology

This paper reports on SiGe NPN HBTs with unity gain cutoff frequency (f/sub T/) of 207 GHz and an f/sub MAX/ extrapolated from Masons unilateral gain of 285 GHz. f/sub MAX/ extrapolated from maximum available gain is 194 GHz. Transistors sized 0.12/spl times/2.5 /spl mu/m/sup 2/ have these characteristics at a linear current of 1.0 mA//spl mu/m (8.3 mA//spl mu/m/sup 2/). Smaller transistors (0.12/spl times/0.5 /spl mu/m/sup 2/) have an f/sub T/ of 180 GHz at 800 /spl mu/A current. The devices have a pinched base sheet resistance of 2.5 k/spl Omega//sq. and an open-base breakdown voltage BV/sub CEO/ of 1.7 V. The improved performance is a result of a new self-aligned device structure that minimizes parasitic resistance and capacitance without affecting f/sub T/ at small lateral dimensions.

SiGe HBTs with cut-off frequency of 350 GHz

This work reports on SiGe HBTs with f/sub T/ of 350 GHz. This is the highest reported f/sub T/ for any Si-based transistor as well as any bipolar transistor. Associated f/sub max/ is 170 GHz, and BV/sub CEO/ and BV/sub CBO/ are measured to be 1.4 V and 5.0 V, respectively. Also achieved was the simultaneous optimization of f/sub T/ and f/sub max/ resulting in 270 GHz and 260 GHz, with BV/sub CEO/ and BV/sub CBO/ of 1.6 V and 5.5 V, respectively. The dependence of device performance on bias condition and device dimension has been investigated. Considerations regarding the extraction of such high f/sub T/ and f/sub max/ values are also discussed.

SiGe HBT technology with f/sub max//f/sub T/=350/300 GHz and gate delay below 3.3 ps

This work reports on SiGe HBT technology with f/sub max/ and f/sub T/ of 350 GHz and 300 GHz, respectively, and a gate delay below 3.3 ps. This is the highest reported speed for any Si-based transistor in terms of combined performance of f/sub max/ and f/sub T/ both of which exhibit 300 GHz and above. Associated BV/sub CEO/ and BV/sub CBO/ are measured to be 1.7 V and 5.6 V, respectively. The dependence of device performance on bias condition and device dimension has been investigated. Considerations regarding the extraction of such high f/sub max/ and f/sub T/ values are also discussed.

A 210-GHz f/sub T/ SiGe HBT with a non-self-aligned structure

A record 210-GHz f/sub T/ SiGe heterojunction bipolar transistor at a collector current density of 6-9 mA//spl mu/m/sup 2/ is fabricated with a new nonself-aligned (NSA) structure based on 0.18 /spl mu/m technology. This NSA structure has a low-complexity emitter and extrinsic base process which reduces overall thermal cycle and minimizes transient enhanced diffusion. A low-power performance has been achieved which requires only 1 mA collector current to reach 200-GHz f/sub T/. The performance is a result of narrow base width and reduced parasitics in the device. Detailed comparison is made to a 120-GHz self-aligned production device.

Foundation of rf CMOS and SiGe BiCMOS technologies

This paper provides a detailed description of the IBM SiGe BiCMOS and rf CMOS technologies. The technologies provide high-performance SiGe heterojunction bipolar transistors (HBTs) combined with advanced CMOS technology and a variety of passive devices critical for realizing an integrated mixed-signal system-on-a-chip (SoC). The paper reviews the process development and integration methodology, presents the device characteristics, and shows how the development and device selection were geared toward usage in mixed-signal IC development.

Manufacturability demonstration of an integrated SiGe HBT technology for the analog and wireless marketplace

Early production results are reviewed for IBMs integrated SiGe HBT technology. With a sample size of over 200 wafers, statistical control of key HBT parameters (F/sub T/, F/sub max/, R/sub bb/, R/sub bi/, /spl beta/) and other supporting devices, and benchmark circuit performance are shown. HBT device yield and reliability on 200 mm wafers are presented, demonstrating that the SiGe HBT is capable of meeting manufacturing requirement for the high performance wireless communications marketplace.

Integrated RF components in a SiGe bipolar technology

Several components for the design of monolithic RF transceivers on silicon substrates are presented and discussed. They are integrated in a manufacturable analog SiGe bipolar technology without any significant process alterations. Spiral inductors have inductance values in the range of /spl sim/0.15-80 nH with typical maximum quality-factors (Q/sub max/) of 3-20. The Q/sub max/s are highest if the doping concentration under the inductors is kept minimum. It is shown that the inductor area is an important parameter toward optimization of Q/sub max/ at a given frequency. The inductors can be represented in circuit design by a simple lumped-element model. MOS capacitors have Qs of /spl sim/20/f (GHz)/C(pF), metal-insulator-metal (MIM) capacitors reach Qs of /spl sim/80/f (GHz)/C(pF), and varactors with a 40% tuning range have Qs of /spl sim/70/f (GHz)/C(pF). Those devices can he modeled by using lumped elements as well. The accuracy of the modeling is verified by comparing the simulated and the measured high-frequency characteristics of a fully integrated, passive-element bandpass filter.

A 0.18 /spl mu/m 90 GHz f/sub T/ SiGe HBT BiCMOS, ASIC-compatible, copper interconnect technology for RF and microwave applications

We present a self-aligned, 0.18 /spl mu/m emitter width SiGe HBT with f/sub T/ of 90 GHz, f/sub MAX/ of 90 GHz (both at V/sub CB/=0.5 V), NF/sub MIN/ of 0.4 dB, and BV/sub CEO/ of 2.7 V. We also demonstrate that this device is integrable with IBMs 0.18 /spl mu/m, 1.8/3.3 V copper metallization CMOS technology with little effect on the CMOS device properties and design rules.

A high reliability metal insulator metal capacitor for 0.18 /spl mu/m copper technology

A high reliability Metal-Insulator-Metal capacitor integrated into a 0.18 /spl mu/m CMOS foundry technology using Copper interconnects is discussed. Integration solutions specific to Copper processing are described and process yield and reliability results are presented on 0.72 fF//spl mu/m/sup 2/ capacitors. Performance and reliability metrics are shown to be comparable to those formed on Aluminum technologies.

SiGe HBT technology: device and application issues

SiGe HBT Bipolar/BiCMOS technology has a unique opportunity in the wireless marketplace because it can provide the performance of III-V HBTs and the integration/cost benefits of silicon bipolar/BiCMOS. This paper will review the status of IBMs SiGe HBT technology particularly focusing on some key device and application issues for high frequency circuit applications. In this work we review graded-base SiGe HBTs optimized for analog circuits and address four key issues: 1) BV/sub ceo/ constraints, 2) Transmission line loss, 3) Noise performance, and 4) Process integration leverage and issues. All of the hardware results are for self-aligned, polysilicon emitter, graded-base SiGe HBTs fabricated in a 200 mm semiconductor production line using the UHV/CVD technique for film growth.