P. Kremer

Bio: P. Kremer is an academic researcher from University of Toronto. The author has contributed to research in topics: Resonator & Surface micromachining. The author has an hindex of 4, co-authored 4 publications receiving 77 citations.

High-Q bulk micromachined silicon cavity resonator at Ka-band

Abstract: A novel bulk silicon micromachining technique for fabricating millimetre-wave waveguide components is presented. This technique enables the formation of deep three-dimensional stacked structures of almost constant cross-section as well as post wafer-bonding metallisation that reduces the effects of air gaps and contact resistances. With these innovations it is possible to realise high-Q devices with low-cost fabrication. Simulated and measured results for a 30 GHz silicon cavity resonator are presented.

A millimeter-wave bandpass waveguide filter using a width-stacked silicon bulk micromachining approach

Abstract: A 30-GHz bandpass filter is realized in a novel waveguide topology, through the use of bulk micromachining of standard (low-resistivity) silicon wafers. In this new design, the width of the rectangular waveguide structure is created through the stacking of etched silicon wafer pieces. This width-stacking approach eliminates the presence of convex corners in the design, resulting in more controllable etching. Also, this design enables the simple implementation of the split-block technique, which alleviates Ohmic contact resistance issues. This latter aspect, combined with a double-sided etching strategy that enables deep cavities to be formed, leads to very high-Q silicon micromachined resonators (Q/sub 0//spl ap/4500). A three-cavity bandpass filter was fabricated and tested leading to a deembedded insertion loss of 1dB at a center frequency of 29.7GHz, with a 3-dB bandwidth of 0.654GHz (2.2%). These results validate this new micromachined waveguide approach, and demonstrates a significant improvement over other millimeter-wave micromachined waveguide filters.

High-Q silicon micromachined cavity resonators at 30 GHz using the split-block technique

Abstract: Bulk micromachining of silicon wafers is a promising technique for use in deep three-dimensional waveguide fabrication. Past efforts to realise a high-quality cavity resonator with such a procedure have resulted in lower than expected unloaded quality factors (Q/sub 0/). A new design for micromachined cavities is presented, that is based upon the split-block technique used in traditional waveguides. Specifically, this design solves poor contact issues involved with the final stages of fabrication encountered in previous topologies of micromachined cavities. Measurement results of four resonant modes between 30 GHz and 52 GHz for a coaxial-fed micromachined cavity are presented. These are compared with simulated values from Ansoft's high frequency structure simulator (HFSS). A measured unloaded Q/sub 0/ of 4550 for the dominant TE/sub 101/ mode at 29.326 GHz compares very well with the simulated value of 4490.

High-Q microstrip-fed bulk micromachined silicon cavities

Abstract: Bulk micromachining of silicon wafers to fabricate rectangular waveguide components has been the focus of much research over the past decade. Over that time, a number of different fabrication techniques have been presented. However, for resonator applications, these fabricated topologies restrict the cavity height to less than two wafer thicknesses. To allow for much deeper cavities, an enabling fabrication procedure for micromachined waveguide components has been proposed. In this paper, a regular height bulk silicon micromachined cavity of constant cross section, fed using a microstrip line, has been presented. The relatively low measured Q/sub 0/ factor for this cavity was due to the poor soldered connections between the top and bottom plates. A new enabling micromachined cavity design has also been introduced, which achieves a very high unloaded (Q/sub 0//spl cong/4500, measured) quality factor.

Waveguide and semiconductor packaging

Abstract: A method and apparatus for integrating individual III-V MMICs into a micromachined waveguide package is disclosed. MMICs are screened prior to integration, allowing only known-good die to be integrated, leading to increased yield. The method and apparatus are used to implement a micro-integrated Focal Plane Array (mFPA) technology used for sub millimeter wave (SMMW) cameras, although many other applications are possible. MMICs of different technologies may be integrated into the same micromachined package thus achieving the same level of technology integration as in multi-wafer WLP integration.

Ka-Band Gap Waveguide Coupled-Resonator Filter for Radio Link Diplexer Application

Abstract: Gap waveguide technology represents an interesting alternative as low-loss, cost-effective, and high-performance transmission line and package of microwave and millimeter-wave systems. A Ka-band coupled-resonator filter for a radio link diplexer, which requires high selectivity to isolate transmit and receiving channels, is proposed and realized using gap waveguide technology. The band-pass filter, which has a central frequency of 37.37 GHz and a pass bandwidth of 560 MHz, is fabricated between two parallel metal plates, leaving an air gap between them. After milling one of the plates, silver-plating is applied on them. Measurements show a minimum in-band insertion loss of 1 dB and agree quite well with simulations.

RF MEMS Circuit Design for Wireless Communications

Abstract: This is the first comprehensive book to address the design of RF MEMS-based circuits for use in high performance wireless systems. A groundbreaking research and reference tool, the book enables you to: understand the realm of applications of RF MEMS technology; become knowledgeable of the wide variety and performance levels of RF MEMS devices; and partition the architecture of wireless systems to achieve greater levels of performance. This innovative resource also guides you through the design process of RF MEMS-based circuits, and establishes a practical knowledge base for the design of high-yield RF MEMS-based circuits. The book features exercises and detailed case studies on working RF MEMS circuits that help you decide what approaches best fit your design constraints. This unified treatment of RF MEMS-based circuit technology opens up a new world of solutions for meeting the unique challenges of low power/portable wireless products.

Millimeter-Wave Dual-Polarized Filtering Antenna for 5G Application

Abstract: This article presents a novel dual-polarized millimeter-wave (mm-Wave) patch antenna with bandpass filtering response. The proposed antenna consists of a differential-fed cross-shaped driven patch and four stacked parasitic patches. The combination of the stacked patches and the driven patch can be equivalent to a bandstop filtering circuit for generating a radiation null at the upper band edge. Besides, four additional shorted patches are added beside the cross-shaped driven patch to introduce another radiation null at the lower band edge. Moreover, by embedding a cross-shaped strip between these four stacked patches, the third radiation null is generated to further suppress the upper stopband. As a result, a quasi-elliptic bandpass response is realized without requiring extra filtering circuit. For demonstration, a prototype was fabricated with standard PCB process and measured. The prototype operates in the 5G band (24.25–29.5 GHz) and it has an impedance bandwidth of 20%. The out-of-band gain drops over 15 dB at 23 and 32.5 GHz, respectively, which exhibits high selectivity. These merits make the proposed antenna a good element candidate for the 5G mm-Wave massive MIMO applications to reduce the requirements of the filters in the mm-Wave RF front ends.

Dielectric Resonator Antenna on Silicon Substrate for System On-Chip Applications

Abstract: This paper presents for the first time the design and performance of a novel integrated dielectric resonator antenna fabricated on a high conducting silicon substrate for system on-chip applications. A differential launcher to excite the TE 01delta mode of the high permittivity cylindrical dielectric resonator was fabricated using the IBM SiGeHP5 process. The proposed antenna integrated on a silicon substrate of conductivity 7.41 S/m has an impedance bandwidth of 2725 MHz at 27.78 GHz, while the achieved gain and radiation efficiency are 1 dBi and 45% respectively. The design parameters were optimized employing Ansoft HFSS simulation software. Very good agreement has been observed between simulation and experimental results. The results demonstrate that integration of dielectric resonator antennas on silicon is viable, leading to the fabrication of high efficient RF circuits, ultra miniaturization of ICs and for the possible integration of active devices.