Johann Heyen

Fully integrated automotive radar sensor with versatile resolution

A planar radar sensor for automotive application is presented. The design comprises a fully integrated transceiver multi-chip module (MCM) and an electronically steerable microstrip patch array. The antenna feed network is based on a modified Rotman-lens. An extended angular coverage together with an adapted resolution allows for the integration of automatic cruise control (ACC), precrash sensing and cut-in detection within a single 77 GHz frontend. For ease of manufacturing the interconnects between antenna and MCM rely on a mixed wire bond and flip-chip approach. The concept is validated by laboratory radar measurements.

Low-cost flip-chip alternatives for millimeter wave applications

This paper discusses alternative flip-chip approaches in the millimeter wave frequency range. In comparison to common stud bumping or gold plating techniques at these frequencies, this contribution deals with bump formation by micro balls and conductive adhesives (polymeric bumps). In the latter process special bump shaping is supported by introducing an additional photoresist process. The photoresist also serves as an underfill for the flip-chip device. Utilizing these bumping techniques, flip-chip test systems in coplanar waveguide (CPW) design were fabricated and then characterized via S-parameter measurements at W-band.