Sychip Inc.

Lucent Technologies Inc.

Liguo Sun

Yinon Degani

Charley Chunlei Gao

Yu Fan

Kunquan Sun

Thomas Dixon Dudderar

Jian Cheng

Meng Zhao

Maureen Lau

Kunguan Sun

The specification describes an integrated passive device (IPD) that is formed on a silicon substrate covered with an oxide layer. Unwanted accumulated charge at the silicon/oxide interface are rendered immobile by creating trapping centers in the silicon surface. The trapping centers are produced by a polysilicon layer interposed between the silicon substrate and the oxide layer.

Integrated passive device substrates

The specification describes a thin film Integrated Passive Device (IPD) design that achieves isolation between conductive runners by shielding the top and bottom regions of a noisy runner with metal shield plates. The shield plates are derived from metal interconnect layers. The invention can be implemented by merely modifying the mask pattern for the metal interconnect layers. No added elements or steps are needed to fabricate the IPDs. The invention is suitable for use in Multi-Chip Modules (MCMs) or other arrangements where digital circuits and RF circuits are in close proximity.

Shielding noisy conductors in integrated passive devices

Balun transformers are described wherein multiple transformer loops are implemented in a stacked design with the primary and secondary loops overlying one another. By aligning the loops in a vertical direction, instead of offsetting the loops, the area of the device is reduced. Multiple transformer loops are nested on each level, and the transformer loops on a given level are connected together using a crossover located on a different level.

Compact balun transformers

The specification describes an MCM package which contains both a digital MCM and an RF MCM in a stacked configuration. The package contains means for isolating RF signals from digital signals. In one case the digital MCM substrate is attached to the system substrate and the RF MCM substrate is attached to the digital MCM substrate. Solder bumps are used for attachment in an arrangement resembling a BGA. For high density packages, at least the digital MCM comprises stacked IC chips. In the embodiment with the RF MCM substrate on the top of the stack, Passive Through Interconnections (PTIs) are made through the digital MCM substrate, and electrically isolated therefrom. The passive through interconnections are made through the solder bumps between boards and interconnected using a passive (with respect to the digital MCM board) through hole. Both the RF ground and the RF input can be isolated using PTIs. For additional isolation, the solder bumps comprising the PTIs are shielded with a Faraday cage. The Faraday cage comprises an array of solder bumps surrounding the solder bump RF conductors.

Stacked module package

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Plano, TX, United States of America

Liguo Sun