Membrane-Templated Flexible Semiconductor Package

Membrane-templated deformable carrier and elastomeric encapsulant enable flexible semiconductor package in support of the demands of wearables and flexible electronic gadgets. The selectively pore-filled membrane, with metal particle suspension, is mechanically reinforced by a thin elastomeric material layer to protect the newly formed leads, and to give structure to withstand package assembly. Package assembly is achieved by attaching a silicon die via a die attach process, electrically connecting the silicon to the carrier via wirebonding, and encapsulating the package using an elastomeric material via elastomeric molding process. The elastomeric support is then peeled off, exposing the terminal surface of the leads. The deformable carrier and the elastomeric encapsulant ensure package flexibility and conformity to distortio

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Embedded Mechanical Interlock into the Silver Plating Layer for Robust Epoxy Molding Compound-To-Carrier Adhesion

Leadless semiconductor package with mechanical interlock is achieved by using a carrier with Cu base material, with selectively plated Ag layer on the leads and the pad. An embedded interlock on the plated layer is introduced, through masking, such that the center of the groove is filled with the plated material or have an enclosed exposed base material surface. The groove/dimple offers a mechanical interlock feature between the exposed Cu base material and/or the plated layer surface, resulting in a stronger adhesion of the epoxy molding compound (EMC) thereby preventing the occurrence of delamination

Cohesive and Interfacial Fractures in Particulate Polymer Composites: Reflow-induced Filler Densification and Epoxy-Filler Adhesion Loss

Heterogeneous viscoelastic materials such as silica or silver particle-filled epoxy glues are important adhesives in the semiconductor and electronics industries. Systems requiring both materials adjacent to each other to satisfy conductive and insulative package requirements are rare, and studies on their compatibility, thermomechanical behavior and reliability are scarce. Herein, we report the analysis of the cohesive and interfacial fracture observed in such systems subjected to mechanical stress, after varying assembly conditions. Filler densification in the conductive glue resulting in an early fail as compared with the non-conductive glue, manifested as an open failure in the simultaneous electrical and mechanical test

Docetaxel epimerization in silicone films : a case of drug excipient incompatibility

Docetaxel (DTX) is an anti-cancer compound derived from 10-deacetyl baccatin III which is indicated for treatment of breast, lung, prostate, gastro-esophageal, and head and neck cancers. Epimerization of DTX at the C-7 hydroxyl position has intrigued chemists and has been implicated in loss of potency, as well as in the development of resistance in tumour cells. For localized controlled delivery of this agent, silicone films were prepared from a commercially available silicone kit. High levels of epimeric degradants were unexpectedly found in the in vitro releasemedia. Herein,we discuss this anomalous DTX degradation to epimeric impurities, and discuss the possible reasons for degradation. Systematic stability studies were performed on the release media and the silicone kit components. It was found that release media and tin-based catalyst present in the silicone kit could be responsible for the epimeric conversion. This unusual case of chemical incompatibility can affect product performance and can even lead to development of resistance in tumour cells towards DTX.

DFT calculation and infrared spectroscopic studies on free-base porphine and meso-substituted porphyrin

Density functional theory (DFT) calculations have been extensively used to study the structures as well as the electronic and vibrational spectra of various compounds. Porphine and its derivatives are biologically and technologically important class of compounds which present interesting signatures in their spectra. We present here the infrared absorption spectrum of free-base 5,10,15,20-tetra-p-tolyl-21H, 23H-porphine. DFT calculations were performed to simulate the equilibrium geometry, energy levels, HOMO-LUMO gap, electrostatic potential map and the IR spectrum of the compound. Comparative analysis with meso-tetrakisphenylporphyrin was performed to evaluate the evolution of symmetry based properties as porphine is functionalized. A brief explanation of the origin of difficulty in the simulation of the properties of such large molecules was also provided