Strained Si/Relaxed SiGe/SiO2/Si 구조 FD n-MOSFET의 전자이동에 Ge mole fraction과 strained Si 층 두께가 미치는 영향

백승혁,심태헌,문준석,차원준,박재근 대한전자공학회 2004 電子工學會論文誌-SD (Semiconductor and devices) Vol.41 No.10

SOI 구조에서 형성된 MOS 트랜지스터의 장점과 strained Si에서 전자의 이동도가 향상되는 효과를 동시에 고려하기 위해 buried oxide(BOX)층과 Top Si층 사이에 Ge을 삽입하여 strained Si/relaxed SiGe/SiO₂Si 구조를 형성하고 strained Si fully depletion(FD) n-MOSFET를 제작하였다. 상부 strained Si층과 하부 SiGe층의 두께의 합을 12.8nm로 고정하고 상부 strained Si 층의 두께에 변화를 주어 두께의 변화가 electron mobility에 미치는 영향을 분석하였다. Strained Si/relaxed SiGe/SiO2/Si (strained Si/SGOI) 구조위의 FD n-MOSFET의 전자 이동도는 Si/SiO₂/Si (SOI) 구조위의 FD n-MOSFET 에 비해 30-80% 항상되었다. 상부 strained Si 층과 하부 SiGe 층의 두께의 합을 12.8nm 로 고정한 shrined Si/SGOI 구조 FD n-MOSFET에서 상부층 strained Si층의 두께가 감소하면 하부층 SiGe 층 두께 증가로 인한 Ge mole fraction이 증가함에 의해 inter-valley scattering 이 감소함에도 불구하고 n-channel 층의 전자이동도가 감소하였다. 이는 strained Si층의 두께가 감소할수록 2-fold valley에 있는 전자가 n-channel 층에 더욱더 confinement 되어 intra-valley phonon scattering 이 증가하여 전자 이동도가 감소함이 이론적으로 확인되었다. In order to enhance the electron mobility in SOI n-MOSFET, we fabricated fully depletion(FD) n-MOSFET on the strained Si/relaxed SiGa/SiO$_2$/Si structure(strained Si/SGOI) formed by inserting SiGe layer between a buried oxide(BOX) layer and a top silicon layer. The summated thickness of the strained Si and relaxed SiGe was fixed by 12.8 nm and then the dependency of electron mobility on strained Si thickness was investigated. The electron mobility in the FD n-MOSFET fabricated on the strained Si/SGOI enhanced about 30-80% compared to the FD n-MOSFET fabricated on conventional SOI. However, the electron mobility decreased with the strained Si thickness although the inter-valley phonon scattering was reduced via the enhancement of the Ge mole fraction. This result is attributed to the increment of intra-valley phonon scattering in the n-channel 2-fold valley via the further electron confinement as the strained Si thickness was reduced.

스마트폰 기반 요검사 스크리닝 애플리케이션

백승혁,최홍락,김경석,Baek, Seung-Hyeok,Choi, Hong-Rak,Kim, Kyung-Seok 한국인터넷방송통신학회 2021 한국인터넷방송통신학회 논문지 Vol.21 No.5

The urinalysis, which is universally accessible to the general public, has disadvantages of being less objective using sight and purchasing a separate portable urinalysis machine. However, due to the high penetration rate and performance improvement of smartphone created by the development of mobile communication technology, research on urinalysis services using smartphone has been conducted. In this paper, a new urinalysis screening application based on smartphone was developed by supplementing the limitations of the previously studied urinalysis services. The key technology of the application is urinalysis recognition algorithm and urinalysis pad color determination algorithm through image-processing and contour detection. In order to confirm the performance of the developed application, urinalysis strip was photographed and analyzed from various backgrounds and angles. 일반인이 보편적으로 접근할 수 있는 요검사는 사람의 눈으로 판단하여 객관성이 떨어지고 별도의 휴대용 요검사기를 구매해야 하는 단점이 있다. 하지만 이동 통신 기술의 발전으로 탄생한 스마트폰의 높은 보급률과 성능 향상으로 스마트폰을 활용한 요검사 서비스에 관한 연구가 진행되었다. 본 논문에서는 앞서 연구된 요검사 서비스들에 대한 제한 사항을 보완하여 새로운 스마트폰 기반 요검사 스크리닝 애플리케이션을 개발하였다. 애플리케이션의 핵심 기술은 이미지 처리와 윤곽선 검출을 통한 요검사지 인식 알고리즘과 요검사 패드 색상 판별 알고리즘이다. 개발한 애플리케이션의 성능을 확인하기 위하여 다양한 배경과 각도에서 요검사지를 촬영하고 분석하였다.

직장암 환자에서 da Vinci® Robot을 이용한 저위방절제술

백승혁,고용택,강창무,이우정,김남규,손승국,조장환 대한외과학회 2007 대한외과학회 학술대회 초록집 Vol.2007 No.5

Development of a Rating System for Digestive System Impairments: Korean Academy of Medical Sciences Guideline

백승혁,이경석,정승용,박영규,김홍수,이동호,오한진,김병천 대한의학회 2009 Journal of Korean medical science Vol.24 No.-

A systematic and effective welfare system for people with digestive system impairments is required. In Korea, an objective and scientific rating guideline does not exist to judge the digestive system impairments. Whether the impairments exist or not and the degree of it need to be examined. Thus, with these considerations we need a scientific rating guideline for digestive system impairments to fit our cultural and social background. In 2007, a research team, for the development of rating impairment guidelines, was organized under the supervision of Korean Academy of Medical Sciences. The rating guidelines for digestive system impairments was classified into upper and lower gastrointestinal tracts impairments and liver impairment. We developed objective rating guidelines for the upper gastrointestinal tract, the impairment generated after surgery for the stomach, duodenum, esophagus, and for the lower gastrointestinal tract, the impairment generated after construction and surgery for colon, rectum, anus, and intestinal stomas. We tried to make the rating impairment guidelines to include science, objectivity, convenience, rationality, and actuality. We especially emphasized objectivity as the most important value. We worked to make it easy and convenient to use for both the subjects who received the impairment ratings and the doctors who will give the ratings.

방송콘텐츠 시장과 수익분배 모형

백승혁,변상규,김광재 한국방송학회 2014 한국방송학회 학술대회 논문집 Vol.2014 No.4

154. 간질환을 동반한 위암 환자의 위절제

백승혁,노성훈,형우진,신동우,허지헌,김충배,민진식 대한외과학회 1999 대한외과학회 학술대회 초록집 Vol.1999 No.11

외란 관측기를 이용한 인휠 모터 자동차의 토크 벡터링 제어 기법

백승혁,김범수,고은영,김진성,황대웅,백주훈 제어로봇시스템학회 2023 제어로봇시스템학회 국내학술대회 논문집 Vol.2023 No.6

A Comprehensive Review of Inflammatory Bowel Disease Focusing on Surgical Management

백승혁,김원호 대한대장항문학회 2012 Annals of Coloproctolgy Vol.28 No.3

The two main diseases of inflammatory bowel disease are Crohn’s disease and ulcerative colitis. The pathogenesis of inflammatory disease is that abnormal intestinal inflammations occur in genetically susceptible individuals according to various environmental factors. The consequent process results in inflammatory bowel disease. Medical treatment consists of the induction of remission in the acute phase of the disease and the maintenance of remission. Patients with Crohn’s disease finally need surgical treatment in 70% of the cases. The main surgical options for Crohn’s disease are divided into two surgical procedures. The first is strictureplasty, which can prevent short bowel syndrome. The second is resection of the involved intestinal segment. Simultaneous medico-surgical treatment can be a good treatment strategy. Ulcerative colitis is a diffuse nonspecific inflammatory disease that involves the colon and the rectum. Patients with ulcerative colitis need surgical treatment in 30% of the cases despite proper medical treatment. The reasons for surgical treatment are various,from life-threatening complications to growth retardation. The total proctocolectomy (TPC) with an ileal pouch anal anastomosis (IPAA) is the most common procedure for the surgical treatment of ulcerative colitis. Medical treatment for ulcerative colitis after a TPC with an IPAA is usually not necessary.

Robotic Colorectal Surgery

백승혁 연세대학교의과대학 2008 Yonsei medical journal Vol.49 No.6

Robotic colorectal surgery has gradually been performed more with the help of the technological advantages of the da Vinci(R) system. Advanced technological advantages of the da Vinci(R) system compared with standard laparoscopic colorectal surgery have been reported. These are a stable camera platform, three-dimensional imaging, excellent ergonomics, tremor elimination, ambidextrous capability, motion scaling, and instruments with multiple degrees of freedom. However, despite these technological advantages, most studies did not report the clinical advantages of robotic colorectal surgery compared to standard laparoscopic colorectal surgery. Only one study recently implies the real benefits of robotic rectal cancer surgery. The purpose of this review article is to outline the early concerns of robotic colorectal surgery using the da Vinci(R) system, to present early clinical outcomes from the most current series, and to discuss not only the safety and the feasibility but also the real benefits of robotic colorectal surgery. Moreover, this article will comment on the possible future clinical advantages and limitations of the da Vinci(R) system in robotic colorectal surgery.

Treatment strategy of palliative surgery for colorectal cancer

백승혁 대한종양외과학회 2012 대한임상종양학회 학술대회지 Vol.2012 No.3