New-Tech Europe Magazine | May 2019

to accommodate the high-speed RF devices. BGA substrate dielectric materials are also a key factor in RF chips. For example, a high-performance liquid polymer substrate, like Rogers laminate, is better suited than the standard FR4 PCB material for use as the substrate for BGA packages used for RF designs. To read a full-length discussion of packaging requirements, please see our white paper, The Ultimate Guide for Selecting an ASIC Package Author Written by Sharon Akler. Sharon has a background in technology and innovation and more than 20 years of experience in global companies and startups. At DELTA, Sharon is looking

between flip chip and wire bond interconnections. Flip chip will provide better RF Performance and enable reaching higher frequencies with lower inductance. Wire bonds, on the other hand, can add a randomly-variable inductance at each RF input or output at higher frequencies. Package layout. At RF frequencies, signals travel along the surface rather than in the conductor. Hence, the way in which the package is assembled has an important effect on the device. For example, high-speed amplifier chips, RF transistors, and diodes often cannot be put into a “standard” plastic package, as the encapsulation materials affect the speed in which the chip operates. Consequently, such chips should go into a cavity QFN or BGA package. High frequency signals (1 GHz and above) are likely to require the layout of the interconnections to have isolated signal paths, known as “ground signal ground” interconnect. Here the requirement of two ground connections for every signal i/o will impact the package size and layout. Additionally, with high-speed ASICs, the signal levels and timing will be affected by the length of the conductor that they travel along. For example, if you are using a BGA package and you have a longer lead to one point and a shorter lead to the next, you will have timing differences on the signal. This must be overcome by putting more consideration into the initial design of the package substrate

after sales in Europe covering ASIC supply chain services. About DELTA Microelectronics With over 25 years of experience, DELTA Microelectronics is a European leader in ASIC services for the semiconductor industry. DELTA's comprehensive services include ASIC design, layout, test development, wafer supply, production testing, package development and assembly, components supply, logistics and supply chain management. DELTA’s development and production facilities are based in Denmark and the UK, with service partners in Europe and Asia. For more information, visit asic.madebydelta.com

Read To Lead

www. new- techeurope . com

New-Tech Magazine Europe l 23