An Investigation of the Effect of the Work-Function Variation of a Monolithic 3D Inverter Stacked with MOSFETs.

The effect of the work-function variation (WFV) of metal-oxide-semiconductor field-effect transistor (MOSFET) gates on a monolithic 3D inverter (M3DINV) structure is investigated in the current paper. The M3DINV has a structure in which MOSFETs are sequentially stacked. The WFV effect of the top- and bottom-tier gates on the M3DINV is investigated using technology computer-aided design (TCAD) and a Monte-Carlo sampling simulation of TCAD. When the interlayer dielectric thickness (TILD) changes from 5 to 100 nm, electrical parameters, such as the threshold voltage, subthreshold swing, on-current, and off-current of the top-tier N-MOSFET and the parameter changes by the change in gate voltage of the bottom-tier P-MOSFET, are investigated. As TILD decreases below about 30 nm, the means and standard deviations of the electrical parameters rapidly increase. This means that the coupling and its distribution are relatively large in the regime and thus should be well considered for M3D circuit simulation. In addition, due to the increase in standard deviation, the WFV effect of both the top- and bottom-tier MOSFET gates was observed to be greater than those of only the top-tier MOSFET gates and only the bottom-tier MOSFET gates.

Advancements in fabrication process of microelectrode array for a retinal prosthesis using Liquid Crystal Polymer (LCP).

Liquid Crystal Polymer (LCP) has been considered as an alternative biomaterial for implantable biomedical devices primarily for its low moisture absorption rate compared with conventional polymers such as polyimide, parylene and silicone elastomers. A novel retinal prosthetic device based on monolithic encapsulation of LCP is being developed in which entire neural stimulation circuitries are integrated into a thin and eye-conformable structure. Micromachining techniques for fabrication of a LCP retinal electrode array have been previously reported. In this research, however, for being used as a part of the LCP-based retinal implant, we developed advanced fabrication process of LCP retinal electrode through new approaches such as electroplating and laser-machining in order to achieve higher mechanical robustness, long-term reliability and flexibility. Thickened metal tracks could contribute to higher mechanical strength as well as higher long-term reliability when combined with laser-ablation process by allowing high-pressure lamination. Laser-thinning technique could improve the flexibility of LCP electrode.

Roles of urology as assessed by an analysis of inpatients referred to urology.

PURPOSE: The purpose of this study was to identify the necessity for professional urology treatment and the roles of urology in the treatment of inpatients referred to the urology department. MATERIALS AND METHODS: The subjects were patients referred to the department of urology among the inpatients of Chosun University Hospital from January 1, 2009, to December 31, 2011. The patients' sex and age, the referring department, and the disease group were extracted from the patients' medical records. Disease groups were classified as urination disorder, infection, tumor, calculus, trauma, pediatrics, andrology, and others. The urination disorder group was classified into the subcategories of neurogenic bladder, benign prostatic hypertrophy, urinary retention, urinary incontinence, and overactive bladder. RESULTS: The total number of referrals was 3,261, and males made up 54.79%. In the age distribution, 2,321 patients (71.17%) were over 60 years of age and the largest population group was patients in their 70s (32.72%). According to the department referring the patients, internal medicine (34.06%) and orthopedic surgery (16.83%) made up a high percentage. Concerning the disease group, urination disorder was the highest, being 61.26%. In the subclassification of the urination disorder group, benign prostatic hypertrophy was the highest category at 32.23%. CONCLUSIONS: In this urology cooperative behavior analysis of our hospital over 3 years, a high percentage of older patients over 60 years of age and a high percentage of urination disorders were found. Urination disorder-related diseases in persons of advanced age are expected to increase as Korea becomes an aged society, and doctors in other departments should be aware that professional treatment and management by a urologist is needed for the treatment of these disorders.