Electrical Characteristics of Flat Cesium Antimonide Photocathode Emitters in Panel Devices

정효수 한국전기전자재료학회 2016 Transactions on Electrical and Electronic Material Vol.17 No.5

The Cs3Sb photocathode was formed by non-vacuum process technology. An in-situ vacuum device was fabricatedsuccessively with flat cesium antimonide photocathode emitters fabricated in a process chamber. The electricalproperties of the device were characterized. Electron emission from the devices was induced by photoemittedelectrons, which were accelerated by an anode electric field that was shielded from the photoemitter surface. Theelectrical characteristics of the devices were investigated by measuring the anode current as a function of deviceoperation times with respect to applied anode voltages. Planar blue LED light with a 450 nm wavelength was used asan excitation source. The results showed that the cesium antimonide photocathode emitter has the potential of longlifetime with stable electron emission characteristics in panel devices. These features demonstrate that the cesiumantimony photocathodes produced by non-vacuum processing technology is suitable for flat cathodes in panel deviceapplications.

Manufacturing of Cs3Sb Photocathode in Atmospheric Conditions

정효수 한국전기전자재료학회 2014 전기전자재료학회논문지 Vol.27 No.10

Cs3Sb photocathode was formed by newly developed process and successive in-situ lightingdevices were fabricated in a process chamber. R, G, and B phosphors were applied on the anode plate,respectively. Major parameters such as brightness, power consumption, and efficacy were measured. Thewavelength of LED excitation source was 450 nm. Both high power and low power modes were appliedin the measurement. Measurement values were clearly differentiated by the voltage application modes. The measured values of each parameter was good enough to be applied for general lighting source. Theresults showed that Cs3Sb photocathode formed in atmospheric conditions was functioning as good as thephotocathode formed in UHV conditions, and thus it could be applied to advanced lighting devices.

Luminous Properties of Planar Lighting Devices Using Cs3Sb Photocathodes

정효수 水原大學校 2015 論文集 Vol.29 No.-

The Cs3Sbphotocathodewasformedby non-vacuum process technology and successive in-situ photocathode vacuum device fabrication was carried out in a process chamber. Performance test of the device was followed. Light emission from the devices was induced by photoemitted electrons, accelerated by an anode electric field that was shielded from the photoemitter surface. The luminescent characteristics of the devices were investigated by measuring the optical parameters as functions of applied anode voltages. The results showed the possibility to produce a more directable and easily controllable stream of light. These make the devices suitable for a variety of planar lighting applications.

Fabrication of a planar UV lighting device utilizing Cs3Sb emitters

정효수 水原大學校 2017 論文集 Vol.31 No.-

Planar UV light sources with uniform intensity are ideal for UV treatments. A newly conceived planar UV lighting device utilizing Cs3Sb mono-alkali antimonide photocathodes as flat electron emitters is here presented and analyzed. The design concept involves a panel device that utilizes photocathodes operated in a reflection mode with an external excitation light source. The excitation light source is in the blue visible light range. Commercially available UV phosphors are used as a light source of desirable UV wavelengths. The light emission characteristics of the device are investigated by measuring the optical parameters as functions of applied anode voltages. The UV light emission shows that cold UV light with the spectral characteristics of near-monochromatic distribution are most effective. It also demonstrates that the UV intensity is sufficient for the UV treatment. More importantly, the planar UV lighting device is mercury free. These make them suitable for all UV applications.

Fabrication of planar lighting devices utilizing Cs3Sb flat emitters

정효수 水原大學校 2018 論文集 Vol.32 No.-

Non-vacuum process technology was used to produce Cs3Sb photocathodes on substrates, and in-situ panel devices were fabricated. The performance of the devices was characterized by measuring the anode current as functions of the devices’operation times. An excitation light source with a 475-nm wavelength was used for the photocathodes. The device has a simple diode structure, providing unique characteristics such as a large gap, vertical electron beam directionality, and resistance to surface contamination from ion bombardment and poisoning by outgassing species. Accordingly, Cs3Sb photocathodes function as flat emitters, and the emission properties of the photocathode emitters depend on the vacuum level of the devices. An improved current stability has been observed after conducting an electrical conditioning process to remove possible adsorbates on the Cs3Sb flat emitters.

보상특성 및 직무특성이 이직의도에 미치는 영향

정효수 한국인사관리학회 2010 한국인사관리학회 학술대회 발표논문집 Vol.2010 No.2

본 연구에서는 보상측면과 직무측면의 특성이 이직의도에 영향을 미치는 영향에 대하여 살펴보았다. 보상 측면에서는 분배공정성과 승진기회의 인식의 이직의도에 대한 부정적인 영향과, 직무 측면에서는 역할갈등과 업무과부하의 의직의도에 대한 긍정적인 영향을 살펴보았다. 또한, 보상 측면의 변수들과 이직의도와의 부정적인 관계에서 조직지원인식과, 성과 보상연계의 조절효과, 직무 측면의 변수들과 이직의도와의 긍정적인 관계에서 직무몰입, 동료의 이직의도의 조절효과를 검증하였다. 가설을 검증한 결과, 분배공정성과 승진기회인식은 이직의도에 부정적인 영향을, 역할갈등과 업무과부하는 이직의도에 긍정적인 영향을 미쳤고, 조직지원인식과 성과보상연계는 승진기회인식과 이직의도와 관계를 조절하였고, 직무몰입은 업무과부하와 이직의도의 관계에서, 동료이직의도는 역할갈등과 이직의도의 관계를 조절하는 것으로 나타났다. 본 연구는 보상과 직무 특성이 이직의도에 대하여 발휘하는 효과를 검증하였다는 점에서 의의가 있으며, 특히 그동안 많이 다루어지지 않은 동료이직의도와 직무몰입이 이직의도에 미치는 효과를 밝혀냈다는 점에서 학문적․실무적 시사점을 갖는다.

Optical Properties of Planar Lighting

정효수 水原大學校 2016 論文集 Vol.30 No.-

This paper presents a concept for a planar light source utilizing Cs3Sb as flat electron emitters. The design concept of the devices with a diode structure was that the photocathodes were to be operated in a reflective mode. Commercially available P-22 phosphors were used as a light source of desirable wavelengths. Light emission from the devices was induced by photoemitted electrons, accelerated by an anode electric field that was shielded from the photoemitter surface. The optical properties of the devices were investigated by measuring the optical parameters as functions of applied anode voltages. The results showed the possibility to produce a more directable and easily controllable stream of light. These make the devices suitable for a variety of planar lighting applications.

포토캐소드를 이용한 발광소자 제작에 관한 연구

정효수 水原大學校 2014 論文集 Vol.28 No.-

상압에서 제조된 포토캐소드(photocathode)를 이용하여 진공소자를 제작하였다. 발광을 위하여 양극기판에 R, G, B 형광체를 도포하였다. 제작된 진공 발광소자에 전압을 인가하여 밝기, 소모전력, 효율 등 발광특성 및 성능을 평가하였다. 전압인가 방식으로는 전류제한이 없는 high power mode와 전류를 제한하는 low power mode를 적용하였다. 전자방출을 유발하는 광원으로는 가시광 영역인 450 nm의 청색 LED 면광원을 사용하였다. 상압에서 제작된 포토캐소드는 전자방출 특성에서 높은 전류밀도와 장기적인 안전성을 나타내었다. 일반적인 포토캐소드 제조와 비교할 때 제작공정이 단순하여 저렴하게 제작할 수 있고, 선택적인 가시광영역의 광원에 감지도가 좋은 특성을 그대로 나타내었다. 제작된 면발광소자는 전압인가 방식에 따라 밝기, 전력소모, 효율 등에서 분명한 차이를 나타내었다. 이것은 응용분야에 적합한 밝기와 전력소모, 효율 등을 선택할 수 있다는 것을 의미한다. 측정된 값은 광원으로 사용하기에 충분한 평가지표를 나타내었다. 따라서 포토캐소드 면발광소자는 일반광원뿐만 아니라 UV 면광원과 같은 첨단 광원개발에 응용될 수 있을 것으로 보인다. 또한, 포토캐소드의 상압 공정기술은 전자원 뿐만 아니라 일반적인 전자소자에도 응용할 수 있을 것으로 보인다.

Fabrication of a Planar UV Lighting Device Utilizing Cs3Sb Photocathode Emitters

정효수 한국물리학회 2017 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.71 No.12

Planar ultraviolet (UV) light sources with uniform intensity are ideal for UV treatments. A newly conceived planar UV lighting device utilizing Cs3Sb mono-alkali antimonide photocathodes as flat electron emitters is presented and analyzed here. The design concept involves a panel device that utilizes photocathodes operated in a reflection mode with an external excitation light source. The excitation light source is in the blue visible light range. Commercially available UV phosphors are used as a light source of desirable UV wavelengths. The light emission characteristics of the device are investigated by measuring the optical parameters as function of applied anode voltage. The UV light emission shows that cold UV light with the spectral characteristics of near-monochromatic distribution are most effective. It also demonstrates that the UV intensity is sufficient for the UV treatment. More importantly, the planar UV lighting device is mercury free. These make them suitable for all UV applications.

Fabrication and Electrical Characterization of Planar Lighting Devices with Cs3Sb Photocathode Emitters

정효수,Kris Keller,Brad Culkin 한국물리학회 2017 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.70 No.6

Non-vacuum process technology was used to produce Cs3Sb photocathodes on substrates, and insitu panel devices were fabricated. The performance of the devices was characterized by measuring the anode current as functions of the devices’ operation times. An excitation light source with a 475-nm wavelength was used for the photocathodes. The device has a simple diode structure, providing unique characteristics such as a large gap, vertical electron beam directionality, and resistance to surface contamination from ion bombardment and poisoning by outgassing species. Accordingly, Cs3Sb photocathodes function as flat emitters, and the emission properties of the photocathode emitters depend on the vacuum level of the devices. An improved current stability has been observed after conducting an electrical conditioning process to remove possible adsorbates on the Cs3Sb flat emitters.