Physicists with the Georgia Institute of Technology report they have stored and retrieved single photons that were transmitted between remote quantum memories.
Copper key to tinier, more-efficient RF circuits
A copper-metallization process that integrates passive devices (IPD) from Stats ChipPAC Ltd., Singapore, boosts performance of RF wireless systems and shrinks them down. Passive-integration technology targets GSM/DCS and CDMA cellular phones, Wireless LAN 802.11 a/b/g, and WiMax systems, primarily in RF-power amplifiers and front-end modules.
IPDs made with conventional ceramic technology tend to be relatively thick and bulky. But passive devices that are integrated and fabricated at the silicon-wafer level are significantly smaller and thinner than their ceramic counterparts. The approach also shrinks matching circuitry and filters.
The process deposits 8 m or more of copper on a silicon wafer. This cuts losses in the RF-signal transmission path, which lowers power consumption and boosts reception. A library of standard IPD elements and custom designs are available. The metallization technology is also integral to the company's Chip Scale Module Package (CSMP) architecture. CSMP integrates mixed IC technologies and passive devices such as resistors, capacitors, inductors, filters, baluns, and interconnects, directly onto a silicon substrate.