Minsu Ko

A scalable 8-channel bidirectional V-band beamformer in 130 nm SiGe:C BiCMOS technology

This paper presents an 8-channel bidirectional 60 GHz beamformer in a SiGe:C 130 nm BiCMOS technology, with f<inf>T</inf>/f<inf>max</inf> = 250/340GHz. The beamformer consists of RF switches, LNAs, PAs, vector modulators, passive dividers / combiners and an integrated SPI controller. On wafer measurements results show that the beamformer has an OP1dB of 0dBm in T<inf>x</inf> mode and an IP1dB of −26 dBm in Rx mode, consuming only 550 mW in both operation modes and occupying a silicon area of 27 mm².

A 220–275 GHz Direct-Conversion Receiver in 130-nm SiGe:C BiCMOS Technology

This letter presents a wideband 240-GHz direct-conversion receiver manufactured in a 130-nm SiGe:C BiCMOS technology with

Multichannel VCSEL-based optical transceiver employing multicore fibers at 6x25 Gbps/fiber (Conference Presentation)

f_{T}/f_{\text {max}}=300

Integrated 240 GHz dielectric sensor with DC readout circuit in THz lab-on-chip measurements

/500 GHz. A mixer-first receiver is implemented, with a new dc offset cancellation loop architecture to compensate for the mixer dc offsets and biasing purposes. A transimpedance amplifier is utilized as a load for the mixer, optimized with the dc offset cancellation loop to maximize the bandwidth. A local oscillator (LO) chain that multiplies by 8 a 30-GHz input signal drives the mixer. The proposed receiver achieves the widest 3-dB bandwidth among the published works of 55 GHz, with a conversion gain of 13 dB. The measured average single-sideband noise figure is 18 dB. It dissipates 500 mW, while occupying 1.25 mm2, requiring LO input signal of only −10 dBm.

A 60 GHz bandwidth differential linear TIA in 130 nm sige:C BiCMOS with < 5.5 pA/√Hz

Multicore fiber enables a parallel optic data link in a single optical fiber. Thus, it is an attractive approach to increase the aggregate data throughput and the integration density of the interconnection. We developed and demonstrated mid-board optical transceiver modules employing novel multicore fiber pigtails and multicore-optimized optoelectronic engines. The silica fibers having 125 µm diameter and including six graded-index multimode cores enable multi-gigabit interconnects at very short distances. The fiber is compatible with the 850-nm VCSEL technology that has many advantages, such as, the very low power operation and the mature and cost-effective GaAs-based device technology. The transceiver incorporates transmitter and receiver subassemblies that are based on the multicore-optimized 850-nm VCSEL and photodiode array chips as well as on the co-designed multichannel VCSEL driver and TIA receiver ICs. All devices are operating up to 25 Gbps/channel and beyond, thus creating a 150 Gbps full-duplex link with the two 6-core fibers. The active areas on the 6-channel VCSEL and PD chips are arranged in a circular array layout that matches the cross-sectional layout of the fiber cores. This allows butt coupling to the fiber cores. The power consumption of the complete link is below 5 mW/Gbps. The transceiver was developed to be applicable for harsh environmental conditions, including space. Therefore, for instance, hermetic packaging was applied and both the active devices and the integration structure enable very wide operation temperature range of up to approx. 100 °C. This paper will present the technical approach including the basic building blocks and the transceiver module implementation. It will also present the results of the data link performance and some reliability testing.

High-Speed SiGe BiCMOS Technologies and Circuits

This paper presents a highly selective integrated dielectric sensor with read-out circuit at 240 GHz in SiGe BiCMOS and back-side etching technology. The sensor features with a resonator to perform bandpass frequency response which varied in accordance to the dielectric change of the sample under test. This variation can be sensed and recorded as the change of output voltage of an integrated 240 GHz IQ receiver. The demonstration of aforementioned function is verified by measuring the output of mixer when a sample is placed over the resonator.

The European project Merlin on multi-gigabit, energy-efficient, ruggedized lightwave engines for advanced on-board digital processors

A differential linear TIA implemented in a 130 nm SiGe: C BiCMOS technology with ft/fmax/BVcEo of 300 GHz/500 GHz/1.7 V is presented. It features a bandwidth of 60 GHz, 62.5 dBO differential transimpedance gain and 5.46 pA/√Hz averaged input-referred current noise density, while dissipating 85 mW of DC power. The measured THD is better than 3% for ∼ 450 mVppd output swing and input current of 400 μApp. Clear NRZ eye diagrams up to 56 Gb/s, as well as PAM-4 eye diagrams up to 30 GBd are also reported. To the authors best knowledge, this design exhibits record low-noise performance among > 50 Gb/s-class silicon-based broadband TIAs towards 100/400 Gb/s optical links.

Integration of 150 Gbps/fiber optical engines based on multicore fibers and 6-channel VCSELs and PDs

This work reports on the development of SiGe-BiCMOS technologies for mm-wave and THz high frequency applications. We present state-of-the-art performances for different SiGe heterojunction bipolar transistor (SiGe-HBT) developments as well as the evolution of complex BiCMOS technologies. With respect to different technology generations of high-speed SiGe-BiCMOS processes at IHP we discuss selected device modifications of the SiGe-HBT to achieve high frequency performances of a complex BiCMOS technology towards the 0.5 THz regime. We show the difference of high-frequency performance difference with respect to maximum achievable transit frequencies fT and oscillation frequencies fmax in comparison to RF-CMOS technologies and depict the required increase of additional process effort for the HBT-module integration for a 0.5 THz SiGe-BiCMOS technology. Moreover different high speed circuits are presented like broadband ICs for optical communication, high frequency circuits for wireless communication at 60 and 240 GHz, mm-wave radar circuits at 60 and 120 GHz as well as THz circuits operating at 245 GHz and 500 GHz for spectroscopic applications. All reviewed circuit examples are based on the discussed 130nm-SiGe-BiCMOS technologies and show their potential for a broad range of high-speed applications.

A Linear Differential Transimpedance Amplifier for 100-Gb/s Integrated Coherent Optical Fiber Receivers

Modern broadband communication networks rely on satellites to complement the terrestrial telecommunication infrastructure. Satellites accommodate global reach and enable world-wide direct broadcasting by facilitating wide access to the backbone network from remote sites or areas where the installation of ground segment infrastructure is not economically viable. At the same time the new broadband applications increase the bandwidth demands in every part of the network - and satellites are no exception. Modern telecom satellites incorporate On-Board Processors (OBP) having analogue-to-digital (ADC) and digital-to-analogue converters (DAC) at their inputs/outputs and making use of digital processing to handle hundreds of signals; as the amount of information exchanged increases, so do the physical size, mass and power consumption of the interconnects required to transfer massive amounts of data through bulk electric wires.

A low-power VCSEL driver in a complementary SiGe:C BiCMOS technology

Multicore fiber enables a parallel optic data link with a single optical fiber, thus providing an attractive way to increase the total throughput and the integration density of the interconnections. We study and present photonics integration technologies and optical coupling approaches for multicore transmitter and receiver subassemblies. Such optical engines are implemented and characterized using multimode 6-core fibers and multicore-optimized active devices: 850-nm VCSEL and PD arrays with circular layout and multi-channel driver and receiver ICs. They are developed for bit-rates of 25 Gbps/channel and beyond, i.e. <150 Gbps per fiber, and also optimized for ruggedized transceivers with extended operation temperature range, for harsh environment applications, including space.