As device dimension shrinks less than 65nm, the propagation delay, crosstalk noises, and power dissipation due to RC (Resistance Capacitance) coupling becomes significant. Cu and LK (Low-k dielectric) material have been introduced to reduce such delays and allow higher device speed and better performance. However, since dielectric material with low-k value usually possesses large amount of porosity, its mechanical properties are degraded significantly which leads to fragile silicon backend structure. This in turn brings in reliability issues like LK cracking due to CPI (Chip Package Interaction). The application of flip-chip packaging introduces significant amount of mechanical stress on BEOL (Back-End-Of-Line) at chip-attach processing step due to CTE mismatch, and makes CPI much more challenging and critical for silicon integration. At advanced technology nodes, increasing performance demand of mobile processors coupled with SoC integration is one major driver of bump pitch reduction [1]. Higher I/O count can be achieved with finer bump pitch since die size very likely stays constant if not shrinking further. Cu pillar and ELK material have been introduced in 28nm to realize the pitch reduction and performance gain. Small UBM structure is required with fine pitch Cu pillar which introduces large amount of stress in BEOL layers. On the other hand, while k-value of ELK is reduced by ~20% compared to LK used in previous technologies, its hardness and mechanical modulus have been reduced by ~30%, resulting in major reduction of ELK material strength. In this paper, we present our key learnings from 28nm CPI development with fine pitch Cu pillar. Empirical data based on CPI TV as well as mechanical stress simulations are discussed. UBM dimension which is a critical factor with Cu pillar from CPI perspective is searched at fine pitch, and our data shows CPI robustness limits pitch reduction with Cu pillar if using standard mass reflow process. ELK robustness is also tested at different process corners, including UBM size, bump height and Cu etching module. Some ELK marginality issues are discovered at certain process corner combinations. CPI margin at 28nm with fine pitch Cu pillar is then assessed by correlating mechanical stress simulation to thermal shock testing data. It is shown that min ~15% ELK margin in terms of max ELK stress is necessary to ensure no ELK delamination happening at process corners. Impact of IMC (Intermetallic Compound) and Ni barrier are also studied. It is found that growth of IMC is critical for ELK integrity with mass reflow process. Once IMC is fully grown between Cu pillar and substrate bonding pad, since its stiffness is 2~3X higher than Lead-free solder, mechanical stress on ELK layers increases dramatically. Additional work is carried out to minimize the growth of IMC. It is confirmed that addition of Ni barrier effectively suppresses IMC growth, and increases CPI margin at process corners by considerable amount. Detailed data is presented and final recommendations on fine pitch Cu pillar conclude the paper.

Despite improved device performance over traditional Poly-SiON technology, high-K metal gate flow introduces additional device variations not previously seen in Poly-SiON process, especially impacting large dimensional (WxL) devices for matching critical applications. For the first time, we report a comprehensive analysis of device variations introduced from metal gate process, GDIM and GGIM, and their sensitivity to circuit layout. Design optimization and verification mechanisms are developed to mitigate metal gate process induced variations in analog matching circuits. After co-optimization, DAC Vt mismatch is reduced by 2.1X and ADC comparator speed is improved by 23.5% in the analog blocks of an advanced mobile SoC currently in production.

This paper summarizes key learnings on 20/16nm CPI (Chip-Package-Interaction) challenges at 100um pitch and below to support ever increasing performance/cost/form factor demands for high performance mobile SoCs. CPI solutions for two types of Cu pillar interconnects using mass reflow and thermal compression type assembly process respectively are studied in technology development/production, and separate bump cell structures are proposed.

Random variations play a critical role in determining SRAM yield, by affecting both the bitcell and the read sense amplifiers (SA). In this work, a process control monitor for SRAM SA offset is proposed and implemented in 28nm LP CMOS technology. The monitor provides accurate measurement of SA offset from a large sample size and accounts for all proximity effects that may affect the SA offset. The all-digital design of the monitor makes it adequate for low voltage testing, high speed data collection, and ease of migration to newer technologies. Detailed measurement results are provided for two of the most commonly used sense amplifiers at different supply and temperature conditions. Statistical yield estimation using the measured sense amplifier offset shows good correlation with measured yield for a 512Kb SRAM. The monitor is a critical part of SRAM silicon yield validation, which is becoming of increasing importance with technology scaling, and the significant increase in random variations.

WormBase (http://www.wormbase.org) is a central data repository for nematode biology. Initially created as a service to the Caenorhabditis elegans research field, WormBase has evolved into a powerful research tool in its own right. In the past 2 years, we expanded WormBase to include the complete genomic sequence, gene predictions and orthology assignments from a range of related nematodes. This comparative data enrich the C. elegans data with improved gene predictions and a better understanding of gene function. In turn, they bring the wealth of experimental knowledge of C. elegans to other systems of medical and agricultural importance. Here, we describe new species and data types now available at WormBase. In addition, we detail enhancements to our curatorial pipeline and website infrastructure to accommodate new genomes and an extensive user base.

In this work we have demonstrated, for the first time, a 0.605µm2 dual core oxide (DCO) dual Vdd 8T SRAM cell in 45LPG triple gate oxide CMOS process for use as L1 cache for high performance low leakage mobile applications. The DCO 8T SRAM operates under dual voltage supplies with write assist. Compared to traditional single-end 8T cell, DCO 8T SRAM showed the same performance with only half the standby leakage, and lower Vccmin. The PU Vt and dual core oxide boundary were optimized to achieve robust Vccmin, process margin and reliability. The 45LPG thin core transistors and the DCO 8T SRAM are able to achieve 1.5GHz speed with ∼500mW at 0.9V and a low Vccmin of 0.6V.

In the advanced Low Power (LP) CMOS technology nodes gate-to-source/drain overlap capacitance (C-OV), gate-to-contact capacitance (C-CO) and gate sidewall fringe capacitance (C-f) have become increasingly important component(s) of transistor parasitic. Accurate extraction and modeling of these parasitic are essential in accurate estimation of circuit performance. In this paper we describe test structure design and extraction of these parasitic components from silicon, which we later correlate to circuit performance. SPICE simulations were performed to substantiate the measurements as needed.

WormBase (www.wormbase.org) is the major publicly available database of information about Caenorhabditis elegans, an important system for basic biological and biomedical research. Derived from the initial ACeDB database of C. elegans genetic and sequence information, WormBase now includes the genomic, anatomical and functional information about C. elegans, other Caenorhabditis species and other nematodes. As such, it is a crucial resource not only for C. elegans biologists but the larger biomedical and bioinformatics communities. Coverage of core areas of C. elegans biology will allow the biomedical community to make full use of the results of intensive molecular genetic analysis and functional genomic studies of this organism. Improved search and display tools, wider cross-species comparisons and extended ontologies are some of the features that will help scientists extend their research and take advantage of other nematode species genome sequences.

WormBase (http://wormbase.org), a model organism database for Caenorhabditis elegans and other related nematodes, continues to evolve and expand. Over the past year WormBase has added new data on C.elegans, including data on classical genetics, cell biology and functional genomics; expanded the annotation of closely related nematodes with a new genome browser for Caenorhabditis remanei; and deployed new hardware for stronger performance. Several existing datasets including phenotype descriptions and RNAi experiments have seen a large increase in new content. New datasets such as the C.remanei draft assembly and annotations, the Vancouver Fosmid library and TEC-RED 5' end sites are now available as well. Access to and searching WormBase has become more dependable and flexible via multiple mirror sites and indexing through Google.

WormBook (www.wormbook.org) is an open-access, online collection of original, peer-reviewed chapters on the biology of Caenorhabditis elegans and related nematodes. Since WormBook was launched in June 2005 with 12 chapters, it has grown to over 100 chapters, covering nearly every aspect of C.elegans research, from Cell Biology and Neurobiology to Evolution and Ecology. WormBook also serves as the text companion to WormBase, the C.elegans model organism database. Objects such as genes, proteins and cells are linked to the relevant pages in WormBase, providing easily accessible background information. Additionally, WormBook chapters contain links to other relevant topics in WormBook, and the in-text citations are linked to their abstracts in PubMed and full-text references, if available. Since WormBook is online, its chapters are able to contain movies and complex images that would not be possible in a print version. WormBook is designed to keep up with the rapid pace of discovery in the field of C.elegans research and continues to grow. WormBook represents a generic publishing infrastructure that is easily adaptable to other research communities to facilitate the dissemination of knowledge in the field.

The human genome sequence defines our inherent biological potential; the realization of the biology encoded therein requires knowledge of the function of each gene. Currently, our knowledge in this area is still limited. Several lines of investigation have been used to elucidate the structure and function of the genes in the human genome. Even so, gene prediction remains a difficult task, as the varieties of transcripts of a gene may vary to a great extent. We thus performed an exhaustive integrative characterization of 41,118 full-length cDNAs that capture the gene transcripts as complete functional cassettes, providing an unequivocal report of structural and functional diversity at the gene level. Our international collaboration has validated 21,037 human gene candidates by analysis of high-quality full-length cDNA clones through curation using unified criteria. This led to the identification of 5,155 new gene candidates. It also manifested the most reliable way to control the quality of the cDNA clones. We have developed a human gene database, called the H-Invitational Database (H-InvDB; http://www.h-invitational.jp/). It provides the following: integrative annotation of human genes, description of gene structures, details of novel alternative splicing isoforms, non-protein-coding RNAs, functional domains, subcellular localizations, metabolic pathways, predictions of protein three-dimensional structure, mapping of known single nucleotide polymorphisms (SNPs), identification of polymorphic microsatellite repeats within human genes, and comparative results with mouse full-length cDNAs. The H-InvDB analysis has shown that up to 4% of the human genome sequence (National Center for Biotechnology Information build 34 assembly) may contain misassembled or missing regions. We found that 6.5% of the human gene candidates (1,377 loci) did not have a good protein-coding open reading frame, of which 296 loci are strong candidates for non-protein-coding RNA genes. In addition, among 72,027 uniquely mapped SNPs and insertions/deletions localized within human genes, 13,215 nonsynonymous SNPs, 315 nonsense SNPs, and 452 indels occurred in coding regions. Together with 25 polymorphic microsatellite repeats present in coding regions, they may alter protein structure, causing phenotypic effects or resulting in disease. The H-InvDB platform represents a substantial contribution to resources needed for the exploration of human biology and pathology.

Adenomatoid tumors are rare benign neoplasms thought to be of mesothelial origin. Although most reported cases arise from the epididymis, rare cases have been reported in the spermatic cord, testicular tunica, ejaculatory ducts, prostate, and suprarenal recess. In female subjects, adenomatoid tumors are commonly found in the uterus and fallopian tubes. Because of the benign nature of this tumor, the treatment of choice is local excision. We describe a rare case of adenomatoid tumor of the testis treated by local excision.

Objectives. Brachytherapy is increasingly used as a treatment for localized prostate cancer but information regarding long-term, postimplantation, patient-reported sexual health-related quality-of-life (HRQOL) is scant. Neoadjuvant hormonal therapy is commonly administered with brachytherapy, yet its potentially adverse effects on subsequent sexual health have not been described using a validated HRQOL instrument. We used a validated HRQOL survey to characterize the significance of neoadjuvant hormonal therapy and other baseline factors on postimplantation sexual function and impairment.Methods. A cross-sectional survey using the expanded prostate cancer index composite HRQOL instrument was administered to all 114 localized prostate cancer patients who underwent ultrasound-guided, transperineal brachytherapy during a 4-year period and to 142 age-matched control men. Multivariable models measured the association of baseline factors and covariates with postimplantation sexual HROOL.Results. Older age (P = 0.01) and neoadjuvant hormonal therapy (P = 0.009) were independently associated with diminished sexual HRQOL after prostate brachytherapy. Among patients younger than 69 years old, 33% reported at least fair sexual function after brachytherapy alone compared with 19% of men after brachytherapy with neoadjuvant hormonal therapy. Of the age-matched control men younger than 69 years old, 78% reported at least fair sexual function. Among patients older than 69 years, 26% reported at least fair sexual function after brachytherapy alone compared with 5% after brachytherapy with neoadjuvant hormonal therapy, and 61% of age-matched controls reported at least fair sexual function,Conclusions. Patient age and neoadjuvant hormonal therapy are independent, significant determinants of sexual HRQOL after prostate brachytherapy. These factors should be taken into consideration when counseling patients with localized prostate cancer regarding the expected, postimplantation sexual HROOL outcome. (C) 2002, Elsevier Science Inc.