MICROSTRUCTURE CHARACTERIZATION OF TiO2 PHOTOELECTRODE FOR DYE-SENSITIZED SOLAR CELL

Lee, Sung Joon 명지대학교 일반대학원 2007 국내석사

상사의 비인격적 행동과 조직문화가 조직냉소주의와 직무소진에 미치는 영향에 관한 연구

김미경 수원대학교 2023 국내박사

The workplace harassment is becoming a big social issue. The workplace harassment ban was enforced from July 2019, and until recently, 3 out of 10 office workers said they had experienced bullying. The supervisor, who is in an prominent position within the organization, acts impersonally to the members, the organizational culture neglects it, and the members keep silence. As a result, it has a negative effect on the organization. Therefore, this study was conducted on the effect of the Abusive Supervision of the supervisor and organizational culture on organizational cynicism and job burnout. In addition, in their influence, the mediating effect of organizational silence and the moderating relationship of social support were analyzed. For data analysis, frequency analysis, validity and reliability analysis by scale, confirmatory factor analysis, correlation analysis, and path analysis were conducted using statistical package programs SPSS and AMOS. Based on the results of the empirical analysis, the following results were found. First, it was found that the abusive supervision of the supervisor and organizational hierarchical culture have a positive (+) effect on organizational silence, but group culture did not have a significant effect on organizational silence. Second, it was found that the abusive supervision of the supervisor and organizational hierarchical culture have a positive (+) effect on organizational cynicism. On the other hand, group culture has a negative (-) effect. Third, it was found that the abusive supervision of the supervisor and the organizational hierarchical culture have a positive (+) effect on job burnout. On the other hand, group culture is analyzed to have a negative (-) effect. Fourth, organizational silence has a positive (+) effect on organizational cynicism and job burnout. Fifth, organizational silence was found to partially mediate the relationship between the supervisor's harsh supervision, organizational culture, organizational cynicism, and job burnout. Sixth, social support was found to have some moderating effects on the impersonal behavior of the supervisor's harsh supervision, organizational culture, organizational cynicism, and job burnout. In this study of people in office workers, it is meaningful in that it presented a organizational silence and the moderating effect of social support in the influence of supervisor' abusive supervision and organizational culture on organizational cynicism and job burnout. In addition, it is analyzed that group culture does not affect organizational silence and has no mediating effect between group culture, organizational cynicism, and job burnout, because organizational members no longer value team unity and team morale.

재가방문 요양보호사들의 직무소진과 이직의도에 관한 연구

송석만 수원대학교 2022 국내석사

In-home care workers, the core personnel of the long-term care insurance system for the elderly, are a very important member of the human resource infrastructure and provide the most extensive and direct services to long-term care recipients. Despite such important roles and necessity of in-home care workers, in-home care workers experience job burnout due to negative employment characteristics such as low professional recognition, poor work conditions, and low-wage short-time work, which are becoming obstacles for them to provide high-quality care services. Exhaustion of in-home care workers is not limited to personal problems but forms negative attitudes and feelings toward recipients, reducing the quality of service. Not properly solving these problems will raise the possibility that the long-term care insurance system for the elderly will fail as a public system. Therefore, this study examined the factors affecting the burnout of in-home care workers for the elderly, what causes their burnout, and whether such burnout influences their turnover intention. Based on the literature review and previous studies, 4 research hypotheses were established, and 24 sub-hypotheses were derived. For the empirical analysis, a survey was conducted on 200 in-home care workers working in home-visited care service institutions. The research results are as follows. First, the analysis result on the relationship between job characteristics and job burnout demonstrated that the job characteristics of in-home care workers did not affect job burnout. This seems to be because in-home care workers mainly provide housework support at home, leading to low relative awareness of the diversity and importance of their jobs. Second, in the analysis of the relationship between role characteristics and job burnout, ambiguity did not have an effect relationship with job burnout, role conflict had a positive (+) effect on emotional exhaustion and dehumanization, and excess role had a positive (+) effect on all of emotional exhaustion, reduced sense of self-fulfillment, and dehumanization. The analysis showed that the biggest reason that in-home care workers feel burnout is excess role. In fact, in-home care workers may have to perform more work than necessary since it is often difficult to reject the heavy service demands of beneficiaries. That in-home care workers are mostly in their 50s and 60s suggest that there are physical limitations in performing services that involve physical labor. Third, the study analyzed the relationship between employment characteristics and job burnout. The result showed that employment instability had a positive (+) effect on all factors of job burnout, which showed that employment insecurity among in-home care workers increases job burnout. In-home care workers are faced with poor work environment factors such as constant job insecurity and low wages, which were reconfirmed through this study. In other words, to improve the level of care services for recipients, it is urgent to improve the employment environment and treatment of in-home care workers in the front line. Fourth, the analysis of the relationship between job burnout and turnover intention indicated that job burnout had a positive (+) effect on turnover intention, suggesting that the more people experience job burnout, the more their turnover intention increases. Emotional exhaustion was especially found to have the highest influence on turnover intention. This result reflects in-home care workers are emotional workers who need to adjust their emotions according to the needs and desires of care recipients.

Probe Card-Type Multizone Electrostatic Chuck Heating Electrode Inspection System

구윤성 명지대학교 대학원 2022 국내석사

Electrostatic chucks (ESCs) are major components of equipment used to improve the production yield of wafers and the temperature uniformity across wafer surfaces by precisely controlling the wafer temperature. However, an ESC is directly exposed to harsh environments such as plasma and chemical gases and the temperature rise and fall of the semiconductor equipment; thus, it may malfunction if used for a certain period. Therefore, repair and performance verification of failed ESCs are desired. In this study, we developed a multizone probe card system suitable for electrical testing of the heating electrodes embedded in ESC control modules to correlate the failure mode factors of ESCs. This system has the advantages of examining the resistance of the internal heating electrode of a 144-zone ESC in a short time and detecting an abnormality in this component based on the measured data. The heating electrode resistance measurement error rate of the developed system was 1%, and the maintenance time was reduced by approximately 66% compared with that of the existing ESC maintenance method. 정전척(ESC)은 웨이퍼 온도를 정밀하게 제어하여 웨이퍼의 생산 수율과 웨이퍼 표면 전체의 온도 균일성을 향상시키는 데 사용되는 장비의 주요 구성 요소입니다. 그러나 ESC는 플라즈마 및 화학 가스와 같은 열악한 환경과 반도체 장비의 온도 상승 및 하강에 직접 노출됩니다. 따라서 일정 기간 사용하면 오작동할 수 있습니다. 따라서 고장난 ESC의 수리 및 성능 검증이 필요합니다. 이 연구에서 우리는 ESC의 고장 모드 요인을 연관시키기 위해 ESC 제어 모듈에 내장된 가열 전극의 전기 테스트에 적합한 다중 구역 프로브 카드 시스템을 개발했습니다. 이 시스템은 144-zone ESC의 내부 발열 전극의 저항을 단시간에 검사하고 측정된 데이터를 기반으로 이 부품의 이상을 감지하는 장점이 있습니다. 개발된 시스템의 발열전극 저항 측정 오차율은 1%로 기존 ESC 유지보수 방식 대비 유지보수 시간이 약 66% 단축되었습니다.

Vertical NAND Flash Memory MOLD층의 플라즈마 식각특성 연구

구중모 명지대학교 대학원 2015 국내석사

For pursuing the rapid and high density device, semiconductor technology has been developed. However, device performance was reach the limit in the planar type because of interference problem which is caused by electrons in 20nm generation device. Instead of planar structure, lately Vertical NAND (V-NAND) flash memory is developed. In this thesis, we studied etch characteristics during MOLD etching process. High Aspect Ratio Contact-hole (HARC) etching and MOLD etching are key factors for plasma etch study. Firstly, we describe bias power effect and chemical characteristic of etching gas in HARC etching. However, low etch depth due to low selectivity of photoresist is unable to distinguish between line patterns and sample cracks. Secondly, we explain the etching gas flow effect, plasma power effect and added gas (Ar, N2, O2) effect in MOLD etching. To investigate characteristics of etching as a function of each condition, other process condition is fixed. In the condition existing added gas, we add the nitrogen gas which does not react with other gas in order to fix process condition. Also, we use the OES sensor so as to get the etch end point information of silicon nitride. During etching process, plasma data like V, I, Phase are acquired. Then, data are converted into plasma power and impedance using Matlab program. In this thesis, when process fault occurs, we can easily notice the chamber condition. So we can control process parameters efficiently. 소비자가 고 성능의 메모리를 추구함에 따라 메모리 제조는 괄목할만한 성장을 이루었다. 또한 메모리 제조공정은 수평적인 거리의 축소를 통해 집적도를 증가시키던 기존의 방법에 한계가 있어 수평적 구조로부터 수직적 구조로 메모리를 제조하는 V-NAND 플래시 메모리가 개발되고 있다. 본 연구에서는 V-NAND 플래시 메모리의 용량을 결정짓는 MOLD층의 식각특성을 알아볼 것이다. MOLD층의 주요 식각특성을 2가지(High Aspect Ratio Contact-hole etching, MOLD etching)로 선정, 그에 따른 샘플을 제작하고 공정특성을 파악한다. HARC etching에선 챔버 바이어스 파워 및 반응물의 화학적 특징에 따른 특성을 파악하려 했으나 공정 장비에 제한이 있고, 미세 패턴의 측정에 문제가 있어 추가 공정이 필요로 했다. MOLD etching에서는 반응 가스 유량, 플라즈마의 파워 전달, 첨가가스에 영향에 따른 식각특성을 알아보고자 했다. 각각의 조건에 따른 식각특성을 파악하기 위해 나머지 공정 조건은 고정시켜 주었고, 첨가된 가스가 존재하는 경우, 반응성이 적은 질소 가스 등의 첨가를 통해 변인통제를 해주었고, 질화막과 산화막의 박막특성의 차이에 따른 영향을 확인하기 위해서 OES센서를 이용해 질화막의 식각종료점을 확인하고자 하였다. 식각공정이 진행되는 동안 하부에 설치된 PIM(Plasma Impedance Monitoring) 센서를 통해 얻은 정보는 데이터 변환을 통해 입력 전압에 따른 플라즈마 파워에 대한 정보를 획득한다. 이 연구를 통해 공정 진행 중 예측하지 못한 결과가 발생하였을 때, 챔버 내의 반응인자인 F라디컬의 분포, 가스유량 및 플라즈마에 작용하는 파워에 대한 영향를 알 수 있기 때문에 공정조건을 임의로 변화시켜주어 결과를 맞춰주던 기존의 방식에서 벗어나, 상황에 맞는 효율적인 공정조건의 변화를 가져올 수 있을 것이다.

Optimization of au (gold) etching by fluoride gases plasma using statistical method

김광범 명지대학교 일반대학원 2009 국내석사

In this paper, reactive ion etching of Au performed with CF₄/Ar gases is presented, and process optimization method is suggested using statistically established process model. I-Optimal design is employed to set up the etch experiment with operating parameters, namely, gas composition, RF power and chamber pressure, and the analysis was performed on etch rate, selectivity, and profile, individually. In addition, the process optimization including all three responses of interest simultaneously is provided. We confirmed that nonvolatile by-product of AuFx was re-deposited on the surface, but the controlling the amount of carbon fluoride provides good etch rate with satisfactory sidewall profile by reducing by-product formation. RF Power is significantly related with etch rate, but increased power gives poor selectivity due to the increased physical etching. Pressure and Gas flows strongly interacts each other, and they affects on sidewall profile. Suggested optimization considers three responses of interests simultaneously, and it is crucial in the process development and optimization for fast ramping up for high volume manufacturing. The additional objective of this study is to develop plasma etching process of Au pattering through statistical modeling employing non-invasive ion energy analyzer (NIEA) data. A series of plasma etching is performed followed by the design of experiment, and ANOVA analysis and response surface analysis, regarding the factors of RF power, Pressure, CF₄, and Ar, are provided. We have noticed that measured ion energy during Au etch is directly related with RF power, and etch rate is also positively proportional to the measured ion energy. 본 논문에서는 CF₄/Ar 가스를 사용하여 Au 박막을 반응성 이온 식각을 하고자 하였고 공정 최적화를 위해 통계적인 모델링 기법을 사용하였다. RF power, 압력 그리고 CF₄/Ar 가스량에 대하여 I-optimal 실험계획법을 사용하여 실험을 실시하였고 etch rate과 profile을 측정하였고 Etch rate과 profile에 있어 통계적인 모델링을 통하여 개별적인 최적화가 아닌 동시에 만족하는 최적조건을 찾을 수 있었다. RF power를 증가 시킬수록 etch rate이 증가하는 경향을 관찰할 수 있었지만 power를 증가시킬수록 물리적 식각의 증가로 낮은 선택비를 가졌다. 압력과 가스량은 서로 교호작용을 관찰할 수 있었으며 profile에 영향을 주는 것을 통계적 모델을 통하여 분석할 수 있었으며 etch rate과 profile을 동시에 만족시킬 수 있는 공정조건을 찾을 수 있었으며 이러한 통계적인 최적화 방법은 큰 스케일의 반도체 양산공정에 효과적으로 적용될 수 있으리라 기대된다. 또한 비접촉식 이온 에너지 분석기를 통하여 플라즈마 이온 에너지를 통하여 Au 박막의 식각 공정을 통계적 모델링 할 수 있었으며 이러한 이온에너지 모델링을 통하여 이온에너지와 RF power, 압력, 가스량의 상관관계를 규명할 수 있었다.

High-speed Impedance Matching with Gradient Descent for an Advanced Radio Frequency Plasma System

신동원 명지대학교 대학원 2023 국내석사

플라즈마 공정은 신기술이 요구하는 더 작고, 더 빠르고, 더 강력한 집적 회로의 제조에 널리 사용된다. 이 연구에서는 RF 임피던스의 매칭 속도를 향상시키기 위해 플라즈마 챔버의 부하 임피던스를 계산하는 새로운 방법을 제안한다. 매칭 상태를 만들기 위해 가변 구성 요소의 목표 값을 계산하기 위해서 IMU의 입력 임피던스와 가변 구성 요소의 임피던스 값을 사용한다. 또한 경사 하강법을 통해서 내부 파라미터의 최적화가 자동으로 이루어지며, 이를 통해서 임피던스 매칭의 정확도를 향상시킨다. 제안된 새로운 매칭 방법은 기존 종래의 기술에 비해 빠른 매칭 시간과 매칭 궤적의 효율성에서 향상된 결과를 보인다. 또한, 매칭 과정에서 플라즈마 불안정성과 매칭 지연을 유발하는 반사 전력의 증가 현상을 억제한다. 이러한 장점들은 향후 플라즈마의 고속 매칭이 필요한 새로운 공정을 개발할 때에 유용하게 사용될 것으로 기대된다. Plasma processes are widely used in the fabrication of integrated circuits for the smaller, faster, more powerful circuits demanded by new technology. To enhance the speed of RF impedance matching, we propose a method for calculating the load impedance of the plasma chamber. To calculate the target value of the variable components, we employ the input impedance of the IMU and the complex impedances of the variable components. In addition, the internal parameters are automatically tuned through the gradient-descent method of machine learning, which improves the accuracy of impedance matching. The new matching method achieved a fast matching time and high efficiency of the matching trajectories. Moreover, it avoids increase of the reflected power during the matching process, which causes plasma instability, and prohibits significant matching delay in a specific area, which disadvantages the conventional matching algorithm. These advantages are expected to significantly expand the development of new plasma processes from that of conventional impedance matching.

VNAND 플래시 메모리 제조 공정에서의 PECVD 공정진단을 위한 RF 신호 모니터링

장동범 명지대학교 대학원 2015 국내석사

반도체 제조산업에서 플라즈마 공정진단 기술에 대한 중요성이 점점 높아져 가고 있다. 공정진단 기술은 웨이퍼 단위간 공정 제어와 in-situ 공정 오류검출을 하기 위해 중요한 역할을 한다. 본 연구에서는 VNAND 플래시 메모리 제조공정 중에 하나인 MOLD 공정에 대한 공정진단 방법을 제시할 것이다. 먼저 PECVD 챔버를 간단한 회로 모델링을 하여 RF 신호와 증착된 박막과의 관계수식을 유도하였다. 이를 통해 챔버 상부와 하부의 RF 신호를 모니터링하는 시스템을 설계하여 PECVD 공정을 모니터링 하였다. 모니터링 시스템은 검출한 RF 신호의 상대적인 변화를 계산하여 출력한다. RF 센서는 반도체 플라즈마 공정을 분석하는데 널리 이용되고 있다. 또한 공정을 모니터링 할 때 플라즈마에 직접적인 영향을 주지 않는 장점을 가지고 있다. MOLD 공정을 진행하기 이전에 산화막과 질화막 단위공정 최적화를 수행하였고, 산화막과 질화막을 반복적으로 증착하여 12 층의 MOLD 구조를 만들었다. 공정 결과를 확인하기 위해 웨이퍼 단면을 SEM으로 측정하였다. 실험 결과 같은 공정조건에서도 상위 층으로 갈수록 증착된 막의 두께가 증가하였으며, RF 센서 데이터에서는 감소하는 경향성을 확인하였다. 이 결과는 전기적 회로 모델링을 통해 연구한 RF 신호와 박막 두께와의 관계식이 성립함을 실험적으로 확인할 수 있었다. 실험 결과를 신뢰하기 위해서는 더 많은 연구가 필요하지만 RF 신호 모니터링을 통해 플라즈마 공정을 진단하여 반도체 제조 품질향상 및 웨이퍼 손실 최소화 효과를 기대할 수 있다. In semiconductor manufacturing industry, plasma process diagnosis technique became more important than before. Process diagnosis is necessary to minimize wafer-to-wafer variation and in-situ process fault detection. In this thesis, we will propose a method for diagnosis of MOLD process which is one of technologies for manufacturing VNAND flash memory. We induced a relation equation between RF signal and thin film thickness using simple circuit modeling. Thus, we developed a system for RF signal monitoring at the upper and lower terminal of chamber. Monitoring system calculates a ratio of change the gain and phase difference. RF sensor is widely used for the analysis of semiconductor plasma processes. Also, it has the advantage of not directly affect the plasma. Before proceeding MOLD process, we first performed a process optimization of oxide and nitride each deposition process. We made a MOLD structure of 12 layers. To confirm the results of the experiment, we measured the cross section of wafer using SEM. The pair thickness is gradually increased according to cycle number of the MOLD process in the same process condition. At the same time, the acquired RF data value showed a trend to decrease. It showed the same trend of the circuit modeling result. In order to increase the accuracy of the results, we will need more experiment. However, based on these studies, it is possible to improve the quality of semiconductor manufacturing and minimize wafer loss.

Abnormal Detection in 3D NAND Dielectrics Deposition Equipment Using Photo Diagnostic Sensor

강대원 명지대학교 대학원 2022 국내석사

As the semiconductor industry develops, the difficulty of newly required process technology becomes difficult, and the importance of production yield and product reliability increases. As an effort to minimize yield loss in the manufacturing process, interests in the process defect process for facility diagnosis and defect identification are continuously increasing. This research observed the plasma condition changes in the multiple oxide/nitride deposition (MOLD) process, which is one of the 3D-NAND manufacturing processes through OES and monitored the result of whether the change in plasma characteristics generated in repeated deposition of oxide film and nitride film could directly affect the film. Based on these results, it was confirmed that if a change over a certain period occurs, a change in the plasma characteristics was detected which may have an effect on the quality of oxide film, such as the film thickness as well as the interfacial surface roughness between the oxide and nitride layer in MOLD. 반도체 산업의 발전함에 따라 새롭게 요구되는 공정기술의 난이도는 어려워지며, 생산수율과 제품의 신뢰성에 대한 중요도는 더욱 높아지게 되었다. 이러한 제조공정상에서 수율 손실을 최소화하기 위한 노력으로 설비 진단 및 결함파악에 대한 공정결함 프로세스에 대해 관심도는 증가하고 있는게 현실이다. 본 연구는 3D-NAND 제조공정 중 하나인 Mold 공정에서의 플라즈마 변화를 OES 를 통하여 관찰함으로써, 산화막과 질화막의 반복적 증착안에서 생겨나는 플라즈마의 특성 변화가 박막에 직접적으로 영향을 줄 수 있는지에 대한 결과를 모니터링 하였다. 이러한 결과를 통해 일정이상의 변화가 발생 될 경우 플라즈마의 특성 변화가 감지되었고 이를 통하여, 산화막에 영향을 미칠 수 있음을 확인하였다.

반도체 플라즈마 식각 장비를 위한 이중 주파수 RF 임피던스 제어 회로 설계

이정수 명지대학교 대학원 2021 국내석사