New liquid crystal polymer (LCP) flex circuits to meet demanding reliability and end-use applications requirements
Flex circuits made from LCP, a thermoplastic polyester, use a newly developed, adhesiveless, roll-to-roll process flow similar to that used for polyimide substrate, including vacuum metallization, additive plating and chemical etching of dielectric. Critical dimensions for both LCP raw test circuits and LCP-coverlayer-laminated LCP test circuits from multiple lots met the specification established for polyimide circuits. LCP circuits have also proven to be dimensionally stable at elevated temperature in common post-circuit operations including die attachment, wire bonding, encapsulation and solder reflow. Trace adhesion was not degraded after solder immersion at 280°C. Wire bonding has proven to be as straightforward as on polyimide, yielding strong wire bonds in a large process window. Integration studies with other materials such as LCP coverlayers and soldermasks that could enable a wide variety of product constructions with multiple materials are going forward. Initial parts passed the entire battery of reliability tests that included moisture resistance, thermal shock and temp-humidity-bias stressing to enable the definition of preliminary process conditions for a wide variety of soldermasks with different polymer chemistries. LCP-based flex circuits should have extended applications beyond those for existing polyimide offerings, due to their reduced moisture uptake and coefficient of humidity expansion and better electrical properties, particularly dissipation factor. These applications include liquid crystal display module (LCDM), medical, high frequency applications, high-density disk drive and integrated circuit packaging.
Liquid Crystal Polymers for Flexible Circuits
The present invention includes the steps of etching a liquid crystal polymer substrate is coated with an aqueous solution comprising: providing a liquid crystal polymer substrate, an alkali metal hydroxide and a solubilizing agent, and the electroless etching using the metal plating or vacuum deposition the liquid crystal of the metal polymer substrate It provides a process for the production of metal-seeded crystal polymer, comprising the step of depositing an adherent metal layer on. When using electroless metal plating, after applying the tin (II) solution to a liquid crystal polymer substrate, by applying a palladium (II) solution to provide a liquid crystal polymer-metal sheathing. An aqueous solution comprising a solubilizing agent of from 35 to 55% by weight of an alkali metal salt and from 10 to 35% by weight of the etchant is provided for a liquid crystal polymer at a temperature of 50 to 120 ℃. Through-hole, and a flexible circuit comprising a liquid crystal polymer film having pores of a relevant configuration it may be formed using an etching composition described above.
Simulating the Illuminance and Efficiency of the LEDs Used in General Household Lighting
Abstract The advantage of the LEDs illumination in general household lighting was proposed. High efficiency white LED as the light source was provided the energy saving illumination of the general household lightings. Different spaces in general household with different standards of average illuminance were designed and simulated by LightTools and DIALux software. The power consumptions and efficiency of traditional illuminated light sources and LED light source in lighting the household environment were analyzed and compared with each other at the same standard of average illuminance. Finally, it provided the advantage of using white LEDs in different spaces of the general household lighting.