This work presents a novel sensor packaging and a novel transition concept for radar applications above 150 GHz based on glass material. By using laser induced deep etching (LIDE) technology, glass vias and cavities are fabricated without degrading the mechanical stability of glass, as micro-cracks are completely avoided. Especially at high millimeter wave (mm-wave) frequencies, precise structuring on low dielectric loss materials and a high integration density are essential for low loss transitions. In this paper, an ultra compact FMCW radar monolithic microwave integrated circuit (MMIC) at 160 GHz is used to demonstrate this packaging technology. In addition, the high frequency signal is guided by a low loss transition to a deposed antenna via a dielectric waveguide (DWG) providing the antenna front end with mechanical flexibility. Thus, using plated through glass vias (TGVs) and a circulating solder ring, the package is hermetically sealed. The optical transparent glass package has a size of only 5.8 mm × 4.4 mm × 0.9 mm. A minimum measured insertion loss of 2.85 dB at 162 GHz from chip to DWG is achieved. The complete radar system with a range resolution of 12 mm is demonstrated via radar measurement.

A novel hermetically sealed RF packaging concept based on glass is presented. Using the laser induced deep etching (LIDE) technology enables the fabrication of glass vias without degrading the mechanical stability as micro-cracks are completely avoided. Furthermore, aspect ratios of up to 1:10 make this technology superior over conventional packaging solutions for the upper millimeter wave regime beyond 150 GHz. As an initial design demonstration, this paper shows a vertical RF-transition through the glass substrate using Through-Glass Vias (TGVs) with an aspect ratio larger than 1:6. The realized prototypes intended for highly efficient LO/VCO distribution within the glass package show excellent reproducibility with a maximum insertion loss of 0.4 dB up to 40 GHz. In addition, a very compact RF-interconnection from PCB to the glass package using solder balls is presented. The simulation of the RF-transition is in good agreement with the measured reflection and transition coefficient not exceeding −15 dB and −1.5 dB up to 35 GHz, respectively.

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In this paper, we present and discuss our new WSi–WSiN–Pt metallization scheme for SiC-based microsystems for applications in harsh environments. Stoichiometric material WSi was selected as contact material for SiC. The diffusion barrier material WSiN was deposited from the same target as the contact material in order to limit the number of different chemical elements in the scheme. Our scheme was kept as simple as possible regarding the number of layers and chemical elements. Our scheme shows very good long-term stability and suitability for SiC-based microsystems. The experimental evaluation concept used here includes a combination of physical, electrical, and mechanical analysis techniques. This combined advance is necessary since modern physical analysis techniques still offer only limited sensitivity for detecting minimal changes in the metallization scheme.