A Flip-Chip Packaging Design With Waveguide Output on Single-Layer Alumina Board for E-Band Applications

Abstract

This paper presents a millimeter-wave packaging design for E-band long-haul point-to-point communications. A broadband flip-chip interconnect with standard 75 µm pad pitch is developed on alumina substrate. To meet the application requirement, a microstrip line to WR-12 waveguide transition is proposed. The transition has no back-short cavity or modified waveguide involved. A back-to-back transition measurement is conducted to characterize the performance. Results show that the working bandwidth is from 69.5 to 87 GHz and the insertion loss at 77 GHz is less than 0.5 dB. A 40-nm CMOS power amplifier is packaged and measured with the proposed packaging design. The entire packaging loss is only 2.5 dB from pads to waveguide, including the loss of a 10 mm microstrip line. The simulated and measured results are in good agreement. The gain and peak output power are 13.4 dB and 17.6 dBm. The silicon temperature is measured as 44.4 • C after saturated output for 30 minutes. The performance is close to probe measurement after deembedding the packaging loss. Comparison between bondwire and flip-chip packaging is discussed and both are verified in millimeter-wave packaging design.

A D-Band 3D-Printed Antenna

“…The continuous phase frequency-shift keying (CPFSK) transmitter is implemented by a 140 GHz digitally controlled oscillator followed up by a power amplifier. This frequency source can deliver up to 7dBm output power, which is then fed to the antenna through a ground-signal-ground (GSG) to waveguide transition delivering a measured output power of 5 dBm at 142 GHz to the antenna [28]. The performance of the system was verified by measuring the effective isotropic radiated power (EIRP) with a subharmonic mixer and spectrum analyzer.…”

Connecting Chips With More Than 100 GHz Bandwidth

“…An overview of the work on flip-chip at mm-wave frequencies until the early 2000 years can be found in [27], demonstrating bandwidths up to 100 GHz (e.g., [28]). Further examples for flip-chip realizations in the mm-wave range present W-band modules for point-to-point communications [29] and on organic substrate [30], solutions for 0 …67 GHz [31], [32] and those for the full band up to 110 GHz [33], [34]. In [35], a transceiver module for imaging applications with 220 GHz bandwidth is presented.…”

“…In [35], a transceiver module for imaging applications with 220 GHz bandwidth is presented. The publications include work on lead-free bumps [33] and underfiller [29], [32]. Also, on a liquid crystal polymer substrate (see [30]), 170 GHz bandwidth have been achieved [36].…”

“…All these works apply one or both of the two design strategies explained in Section II, i.e., miniaturizing the bump interconnect and using compensation techniques to further reduce influence of the parasitics [29], [32], [34].…”

Si-based system-in-package design with broadband interconnection for E-band applications

“…E-band communication systems covering 71-76 GHz and 81-86 GHz frequency bands have drawn great attention in recent years [1,2,3,4,5,6]. As the frequency is up to millimeter-wave (MMW) bands, the size of antenna is comparable with RF chips, which makes the integration of chips and antenna possible.…”