Solenoidal Transformers for Magnetic Materials Integration

Lamine Ourak (1) , Ayad Ghannam (1) , David Bourrier (2) , Christophe Viallon (1) , Thierry Parra (1)

1 LAAS-MOST - Équipe Microondes et Opto-microondes pour Systèmes de Télécommunications
2 LAAS-TEAM - Service Techniques et Équipements Appliqués à la Microélectronique

This paper presents the design, fabrication and characterization of suspended solenoidal transformers fabricated using a low cost single step 3D copper electroplating process. The design and optimization of solenoidal transformers with and without magnetic core are performed using HFSS. After optimization, the suspended structures reveal good electrical performance. The addition of a magnetic core to these structures shows a significant improvement of its electrical properties. Thus, an increase of 10% on Gmax, 20% on coupling coefficient k, 80% on the quality factor Q and 350% on the inductance is observed. Under probe measurements carried on the suspended structures without magnetic core exhibit a Gmax of -1.45 dB and a Q of 28.5 at 2.5 GHz. The enhanced performance coupled with the low cost 3D process makes these transformers excellent candidates for today s RF applications.

Mots clés: Above-IC; magnetic core; solenoids; three-dimensional integrated circuits; transformers

Domaines: Electronique

Lamine Ourak, Ayad Ghannam, David Bourrier, Christophe Viallon, Thierry Parra. Solenoidal Transformers for Magnetic Materials Integration. 2012 Asia-Pacific Microwave Conference, Dec 2012, Kaohsiung, Taiwan. p1 - 4, ⟨10.1109/APMC.2012.6421757⟩. ⟨hal-00783047⟩