A Fully Embedded LTCC Multilayer BPF for 3-D Integration of 40-GHz Radio

Abstract

This paper demonstrates a low loss fully embedded multilayer bandpass filter (BPF) using low-temperature cofired ceramic (LTCC) technology for 3-D integration of 40-GHz multimedia wireless system (MWS) radio. The LTCC filter implemented in a stripline configuration occupies an area of only 5.5 2.3 0.6 mm including shielding structure and coplanar waveguide (CPW) transitions. The measured insertion loss was as small as 1.9 dB at a center frequency of 41.8 GHz, and the return loss was 12.2 dB including the loss associated with two CPW-to-stripline transitions. This six-layer BPF showed 3-dB bandwidth of 10.5% from 39.6 to 44.0 GHz at a center frequency of 41.8 GHz and suppressed the local oscillator (LO) signal to 20.2 dB at a local oscillator frequency of 38.8 GHz, making it suitable for the 40 GHz MWS applications.Index Terms-Bandpass filter (BPF), embedded, low-temperature cofired ceramics (LTCC), multilayer, multimedia wireless systems (MWS).

Low-Temperature Sintering and Microwave Dielectric Properties of Zn2SiO4 Ceramic Added with Crystalline Zinc Borate

“…1 LTCC-based circuits have been widely used for microwave circuit applications in the 1-40 GHz frequency range. 2 These microwave circuits and components are mostly used in front end modules for mobile phones, wireless local-area networks, local multi-point distribution systems, a variety of RF modules, radar, antenna circuits, and Bluetooth modules with integrated antennas, among other applications. [3][4][5][6] Most of these applications use commercially available LTCC material systems, for example DuPont 951, 943 and 9k7, or Ferro A6M.…”

LTCC Ka-band bandpass filters with half-wavelength inverted-L stubs

“…LTCC technology is useful for constructing multilayer filters with reduced size and improved performance [5 , -8]. Cho et al [5] proposed a fully embedded multilayer LTCC filter for 40-GHz band applications with stripline resonators and coplanar waveguide-to-stripline transitions. Ambak et al [6] presented a 40-GHz LTCC bandpass filter with multilayer end-coupled resonators.…”

Five-pole LTCC cavity filter for wireless applications at 34GHz

“…Various highly integrated multilayer technologies such as low and high temperature co-fired ceramic (LTCC and HTCC) and MCM-D have been the most suitable technologies for implementing a complete SOP solution. However, LTCC technology is currently being studied to achieve complete SOP solutions [3]. The 3D integration of all the DC power lines, analog circuits, high-speed digital logic circuits, and RF/microwave components into a multi-layer environment has become the trend and a common target for many of these mixed-signal products.…”

“…In the Fig.1 (a) the embedded BPF is connected with next active monolithic mirowave integrated circuits (MMICs) while in the (b) the traditional off-chip BPF requires additional assemblies such as flip-chip or wire bonding [3] . Due to its' vertiacl structure, 3-D integrated cavity filter is selected as embedded filter in the SOP.…”