LTCC phase shifter modules for RF-MEMS-switch integration

The European 1ST project ARHMS is covering a wide field of R&D activities with the final goal: a satellite based car communication system with a fiat electronically steerable roof antenna based on RF-MEMS. The required phase shift for beam steering will be done with MEMS switches and RF networks. An integratable LTCC packaging and wiring module with the MEMS and the passives has to be placed and connected close to the patch antenna. LTCC as a ceramic interconnection technology for processing multilayer boards, multi-chip-modules and packages, enables increased circuit density and high reliable structures. Within this work the good integration opportunities and the low loss of LTCC were reasons for the choice as well as thermal conductivity and the possibility to build cavities and windows, to integrate the RF-switches and SMDs and to guide the RF signal in a power range around 5 watt (Tx). Initial material studies and investigation, simulations of the RF conditions, technology improvements in structuring and processing LTCC as well as numerous test runs and measurements had been done to develop an initial test substrate. These early test structures were used to verify the design and simulation surrounding. The extracted correlation data allow the most promising layout work. Copyright © 2005 IMAPS

Autoclaveable miniaturized video endoscopes with simplified flip-chip assembly

Miniaturized video endoscopes with an imager located at the distal end and a simplified opto-mechanical layout are presented. They are based on a CMOS imager with 650 x 650 pixels of 2.8 ?m pitch and provide straight view with 75 ° and 110 ° field of view at f/4.3. They have an outer diameter of 3 mm including the shell and a length of approx. 8 mm. The optics consist of polymer lenses in combination with a GRIN and a dispensed lens. Using a simple flip chip assembly, optical axis alignment better than 10 ?m and a contrast of 30 % at 90 LP/mm was achieved. The 75 ° FOV system was sealed at the front window using a solderjetting technology, providing 10-9 mbar*l/s leakage rates even after several autoclave cycles