KR20010059316A - Image sensor structure to improved photo sensitivity and method for fabricating the same - Google Patents
Image sensor structure to improved photo sensitivity and method for fabricating the same Download PDFInfo
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- 229910052721 tungsten Inorganic materials 0.000 claims description 3
- 239000010937 tungsten Substances 0.000 claims description 3
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- 229910052751 metal Inorganic materials 0.000 description 13
- 206010034960 Photophobia Diseases 0.000 description 6
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Abstract
Description
본 발명은 이미지센서 및 그 제조방법에 관한 것으로, 특히 입사하는 광을 효과적으로 집광할 수 있도록 구현된 이미지센서 및 그 제조방법에 관한 것이다.The present invention relates to an image sensor and a method for manufacturing the same, and more particularly, to an image sensor and a method for manufacturing the same so as to effectively collect incident light.
일반적으로, 이미지센서(image sensor)라 함은 광학 영상(optical image)을 전기 신호로 변환시키는 반도체소자로서, 이중 전하결합소자(charge coupled device: 이하 CCD)는 개개의 MOS(Metal-Oxide-Silicon: 이하 MOS) 커패시터가 서로 매우 근접한 위치에 있으면서 전하 캐리어가 커패시터에 저장되고 이송되는 소자이며, CMOS(Complementary MOS; 이하 CMOS) 이미지센서는 제어회로(control circuit) 및 신호처리회로(signal processing circuit)를 주변회로로 사용하는 CMOS 기술을 이용하여 화소수만큼 MOS트랜지스터를 만들고 이것을 이용하여 차례차례 출력(output)을 검출하는 스위칭 방식을 채용하는 소자이다.In general, an image sensor is a semiconductor device that converts an optical image into an electrical signal, and a charge coupled device (CCD) is an individual metal-oxide-silicon (MOS). Is a device in which charge carriers are stored and transported in a capacitor while the capacitors are in close proximity to each other, and a CMOS (Complementary MOS) image sensor is a control circuit and a signal processing circuit. Is a device that adopts a switching method that makes MOS transistors by the number of pixels by using CMOS technology using peripheral circuits, and sequentially detects the output by using the same.
이러한 다양한 이미지센서를 제조함에 있어서, 이미지센서의 광감도(photo sensitivity)를 증가시키기 위한 노력들이 진행되고 있는 바, 그 중 하나가 집광기술이다. 예컨대, CMOS 이미지센서는 빛을 감지하는 광감지부분과 감지된 빛을 전기적 신호로 처리하여 데이터화하는 로직회로부분으로 구성되어 있는바, 광감도를 높이기 위해서는 전체 이미지센서 면적에서 광감지부분의 면적이 차지하는 비율(Fill Factor)을 크게 하려는 노력이 진행되고 있지만, 근본적으로 로직회로 부분을 제거할 수 없기 때문에 제한된 면적 하에서 이러한 노력에는 한계가 있다.In manufacturing such various image sensors, efforts are being made to increase the photo sensitivity of the image sensor, and one of them is a light condensing technology. For example, the CMOS image sensor is composed of a light sensing portion for detecting light and a logic circuit portion for processing the detected light as an electrical signal to make data. In order to increase the light sensitivity, the area of the light sensing portion occupies the entire area of the image sensor. Efforts have been made to increase the fill factor, but these efforts are limited in a limited area because the logic circuit part cannot be removed fundamentally.
도1은 종래기술에 의한 집광기술을 보여주는 종래의 이미지센서 단면도로서, 도1에는 집광에 관련된 이미지센서의 주요부분만이 개략적으로 도시되어 있다.Figure 1 is a cross-sectional view of a conventional image sensor showing a condensing technique according to the prior art, Figure 1 schematically shows only the main part of the image sensor related to the condensing.
도1을 참조하면, 종래의 이미지센서는 소자분리절연막(2)이 형성된 실리콘기판(1) 표면 하부에 수광소자로서 포토다이오드(3)가 형성되고 그밖에 이미지센서를 구성하는 NMOS 및 PMOS 트랜지스터 등의 CMOS 소자(도면에 도시되지 않음)들이 형성된다. 소자분리절연막(2) 상에 형성된 패턴은 트랜지스터의 게이트전극 패턴시 형성된 워드선(4)을 나타낸다. 이어 금속배선전절연막(PMD : pre metal dielectric)(5)이 형성되고, 제1금속배선(6)이 형성되며 다시 금속배선간절연막(IMD : inter metal dielectric)(7)이 형성된 후 제2금속배선(8)이 형성된다. 금속배선은 단층 또는 3층 배선으로 형성될 수도 있다. 이어 소자보호막(9)이 형성되고 소자보호막 상에 칼라필터(calor filter)(10)가 형성된다. 칼라필터는 레드(R), 그린(G) 및 블루(B)의 3가지 칼라필터가 어레이되어 형성된다. 이어 칼라필터어레이 상에 평탄화 및 초점거리 조절을 위한 버퍼층(11)이 형성되고 그 위로 마이크로렌즈(12)가 형성된다.Referring to FIG. 1, in the conventional image sensor, a photodiode 3 is formed as a light receiving element under the surface of the silicon substrate 1 on which the device isolation insulating film 2 is formed, and other NMOS and PMOS transistors constituting the image sensor, etc. CMOS elements (not shown in the figure) are formed. The pattern formed on the element isolation insulating film 2 represents the word line 4 formed during the gate electrode pattern of the transistor. Subsequently, a pre metal dielectric (PMD) 5 is formed, a first metal wiring 6 is formed, and an inter metal dielectric (IMD) 7 is formed, and then a second metal is formed. The wiring 8 is formed. The metal wiring may be formed by single layer or three layer wiring. Subsequently, a device protection film 9 is formed, and a color filter 10 is formed on the device protection film. The color filter is formed by arranging three color filters of red (R), green (G), and blue (B). Subsequently, a buffer layer 11 for planarization and focal length adjustment is formed on the color filter array, and a microlens 12 is formed thereon.
통상적으로 칼라필터(10)의 재료로는 염료가 첨부된 레지스트가 주로 이용되고 있으며, 마이크로렌즈(12)의 재료로는 레지스트 또는 그와 유사한 수지(resin)가 주로 이용된다. 또한, 금속배선전절연막(5), 금속층간절연막(9) 및 소자보호막(9)은 광투과 절연막으로서 각각 단층 또는 다층의 산화물계 박막 또는/및 질화물계 박막이 적용된다. 그리고, 버퍼층(11) 역시 광투과물질로서 산화물계 박막 또는 포토레지스트가 적용된다.Generally, a resist with dye is mainly used as the material of the color filter 10, and a resist or a similar resin is mainly used as the material of the microlens 12. In addition, the metal interconnection insulating film 5, the metal interlayer insulating film 9, and the element protective film 9 are applied with a single layer or a multilayer oxide thin film and / or nitride thin film, respectively, as a light transmissive insulating film. In addition, an oxide thin film or a photoresist is applied to the buffer layer 11 as a light transmitting material.
한편, 마이크로렌즈(12)는 단위화소의 크기와 위치, 모양, 그리고 포토다이오드까지의 깊이, 그리고 금속배선의 높이, 위치, 크기 등에 의해 결정되는 최적의 크기와 두께 그리고 곡률반경으로 형성되어야 한다.On the other hand, the microlens 12 should be formed with an optimal size, thickness, and radius of curvature determined by the size, position, shape of the unit pixel, the depth to the photodiode, and the height, position, size, etc. of the metal wiring.
그러나, 점점 이미지센서가 고집적화 되어감에 따라 역시 단위화소의 크기가 축소되면서 마이크로렌즈의 크기도 그에 따라 축소되며 또한 마이크로렌즈로부터 포토다이오드까지의 깊이는 깊어지게 되는 바, 이에 의해 마이크로렌즈가 정확한 광집속 기능을 수행하도록, 즉 원하는 포토다이오드에 정확히 광을 집속하도록, 그 두께 및 곡률 반경 등을 설정하기가 매우 어렵게 된다.However, as the image sensor becomes more and more highly integrated, the size of the unit pixel is also reduced, and the size of the microlens is reduced accordingly, and the depth from the microlens to the photodiode is deepened. It is very difficult to set the thickness, the radius of curvature, and the like so as to perform the focusing function, that is, to accurately focus light to a desired photodiode.
또한, 원하는 포토다이오드에 정확히 광이 집속되지 않고 벗어나므로써 어레이된 포토다이오드들 끼리의 광감도가 균일하지 않게 된다. 즉, 각 단위화소에 형성되는 마이크로렌즈는 각 단위화소의 포토다이오드에 일정하게 정렬되기 때문에 가운데와 외곽 단위화소의 광감지소자에 도달하는 광의 양이 다르게되어 광감도의 불 균일도를 가져온다.In addition, since light is not focused on the desired photodiode, the light sensitivity of the arrayed photodiodes is not uniform. That is, since the microlenses formed in each unit pixel are constantly aligned with the photodiodes of each unit pixel, the amount of light reaching the photosensitive elements of the center and outer unit pixels is different, resulting in unevenness of light sensitivity.
아울러, 포토다이오드 상부에는 다층의 절연막들이 적층되어 있으므로 마이크로렌즈를 통과하여 집광되는 빛이 다층 절연막 계면에서 반사 및 흡수되어 손실되므로써 광감도가 떨어지는 문제점도 갖고 있다.In addition, since multilayer insulating films are stacked on the photodiode, light collected through a microlens is reflected and absorbed and lost at the interface of the multilayer insulating film.
본 발명의 다층의 절연층들에 의해 광이 손실되는 것을 방지하고 아울러 마이크로렌즈를 통해 입사된 광이 포토다이오드 외곽 방향으로 진행하는 것을 다시집광하도록 하여 광감도를 크게 향상시킨 이미지센서 및 그 제조방법을 제공하는데 있다.An image sensor and a method for manufacturing the same, which prevent the light from being lost by the multilayer insulating layers of the present invention and condense the light incident through the microlens to travel in the outward direction of the photodiode, thereby greatly improving the light sensitivity. To provide.
도1은 종래기술에 의한 이미지센서의 구조 및 집광 경로를 보여주는 단면도,1 is a cross-sectional view showing a structure and a condensing path of an image sensor according to the prior art;
도2a 내지 도2d는 본 발명의 일 실시예에 따른 이미지센서 제조 공정도,2a to 2d is an image sensor manufacturing process according to an embodiment of the present invention,
도3a 및 도3b는 본 발명의 다른 실시예에 따른 이미지센서 제조 공정도.3a and 3b is an image sensor manufacturing process according to another embodiment of the present invention.
* 도면의 주요부분에 대한 부호의 설명* Explanation of symbols for main parts of the drawings
1 : 실리콘기판 2 : 소자분리절연막1: silicon substrate 2: device isolation insulating film
3 : 포토다이오드 4 : 워드선3: photodiode 4: word line
5 : 금속배선전절연막 6 : 제1금속배선5: Pre-insulation film of metal wiring 6: First metal wiring
7 : 금속층간절연막 8 : 제2금속배선7 interlayer insulating film 8 second metal wiring
9 : 소자보호막 10 : 칼라필터9 element protection film 10 color filter
11 : 버퍼층 12 : 마이크로렌즈11 buffer layer 12 microlens
13 : 홈 14 : 절연막스페이서13 groove 14 insulating film spacer
15 : 반사층 16 : 평탄화 절연막15 reflective layer 16 planarization insulating film
상기 목적을 달성하기 위한 본 발명의 이미지센서는, 포토다이오드 또는 포토게이트 등의 광감지소자가 형성된 기판; 상기 기판 상에 형성되되 상기 광감지소자 상부에서 홈을 갖는 다층의 제1절연막; 상기 홈의 측벽에 형성된 제2절연막; 상기 홈내의 상기 제2절연막 측벽에 형성되어 외부로부터 입사되는 광을 상기 광감지소자로 집속하는 반사층; 상기 반사층이 형성된 기판 전면에 형성되어 평탄화된 제3절연막; 상기 제3절연막 상에 상기 포토다이오드에 대향하여 형성된 칼라필터; 및 상기 칼라필터 상에 형성된 마이크로렌즈를 포함하여 이루어짐을 특징으로 한다.The image sensor of the present invention for achieving the above object is a substrate on which a photosensitive device such as a photodiode or photogate is formed; A multi-layered first insulating layer formed on the substrate and having a groove on the photosensitive device; A second insulating film formed on the sidewall of the groove; A reflection layer formed on the sidewall of the second insulating layer in the groove to focus light incident from the outside onto the photosensitive device; A third insulating layer formed on the entire surface of the substrate on which the reflective layer is formed and planarized; A color filter formed on the third insulating layer to face the photodiode; And a microlens formed on the color filter.
또한 본 발명의 이미지센서는, 광감지소자가 형성된 기판; 상기 기판 상에 형성되되 상기 광감지소자 상부에서 홈을 갖는 다층의 제1절연막; 상기 홈의 측벽에 형성된 제2절연막; 상기 홈내의 상기 제2절연막 측벽에 형성되어 외부로부터 입사되는 광을 상기 광감지소자로 집속하는 반사층; 상기 반사층이 형성된 홈 내부를 매립하는 칼라필터; 및 상기 칼라필터 상에 형성된 마이크로렌즈를 포함하여 이루어짐을 특징으로 한다.In addition, the image sensor of the present invention, the substrate on which the light sensing element is formed; A multi-layered first insulating layer formed on the substrate and having a groove on the photosensitive device; A second insulating film formed on the sidewall of the groove; A reflection layer formed on the sidewall of the second insulating layer in the groove to focus light incident from the outside onto the photosensitive device; A color filter filling the inside of the groove in which the reflective layer is formed; And a microlens formed on the color filter.
이하, 본 발명이 속하는 기술분야에서 통상의 지식을 가진자가 본 발명의 기술적 사상을 용이하게 실시할 수 있을 정도로 상세히 설명하기 위하여, 본 발명의 가장 바람직한 실시예를 첨부된 도면을 참조하여 설명하기로 한다. 이해를 돕기 위하여 종래기술과 동일한 구성요소는 동일한 도면부호를 인용하였다.DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art may easily implement the technical idea of the present invention. do. To aid understanding, the same components as in the prior art have been referred to by the same reference numerals.
도2a 내지 도2d는 본 발명의 일 실시예에 따른 이미지센서 제조 공정도이다.2A to 2D are process diagrams for manufacturing an image sensor according to an exemplary embodiment of the present invention.
먼저, 도2a는 통상적인 방법으로 칼라필터를 형성하기 직전까지의 공장을 진행한 상태의 단면도로서, 최상부층인 소자보호막(9) 상에 포토다이오드의 상부 영역이 오픈된 마스크를 사용하여 상기 소자보호막(9), 금속층간절연막(7), 금속배선전절연막(5)의 일부두께를 식각하여 홈(13)을 형성한다. 이때, 포토다이오드(3)와 홈(13)의 저부가 서로 맞닿지 않도록 식각정도를 조절한다. 상기 홈(13)은 하부로 갈수록 그 오픈 폭이 좁아지도록 경사진 쐐기형 홈이 될수도 있다. 본 실시예에서는 3층의 절연막을 도시하고 있으나 소자보호막 상에는 별도로 평탄화 등을 위한 버퍼층이 더 형성될 수 있고, 절연층 역시 다층으로 형성될 수 있다.First, Fig. 2A is a cross-sectional view of a factory that proceeds until just before forming a color filter in a conventional manner, by using a mask in which an upper region of a photodiode is opened on an element protective film 9, which is the uppermost layer. The grooves 13 are formed by etching some thicknesses of the protective film 9, the interlayer insulating film 7, and the pre-metal wiring insulating film 5. At this time, the degree of etching is adjusted so that the bottoms of the photodiode 3 and the groove 13 do not contact each other. The groove 13 may be a wedge-shaped groove that is inclined so that the opening width thereof becomes narrower toward the lower portion. In this embodiment, three insulating layers are illustrated, but a buffer layer for planarization may be further formed on the device protection layer, and the insulating layer may also be formed in multiple layers.
이어서, 도2b에 도시된 바와 같이, 홈(13)의 측벽에 절연막스페이서(14)를 형성한다. 이 절연막스페이서(14)는 홈의 측벽에 얼라인 미스 또는 레이아웃상 배선이 노출될 수도 있으므로 이들을 후속공정에서 증착되는 반사층(금속)과 절연시키기 위한 것이다. 여기서 절연막스페이서 대신에 얇은 절연막을 증착한 상태로 놔둘 수도 있다. 그렇지만 광 반사 및 흡수를 최소화하기 위하여 포토다이오드 상에 되도록 다층으로 절연층이 형성되지 않도록 하기 위해서는 비등방성 전면식각에 의해 스페이서로 형성하는 것이 바람직하다. 절연막스페이서로는 산화막, 질화막 또는 산화질화막 등을 사용하는 것이 가능하다.Subsequently, as shown in FIG. 2B, an insulating film spacer 14 is formed on the sidewall of the groove 13. The insulating film spacer 14 is intended to insulate the insulating layer 14 from the reflective layer (metal) deposited in a subsequent step since the alignment miss or layout wiring may be exposed on the sidewall of the groove. The thin insulating film may be left in place of the insulating film spacer. However, in order to prevent the insulating layer from being formed in multiple layers on the photodiode in order to minimize light reflection and absorption, it is preferable to form the spacer by anisotropic front etching. As the insulating film spacer, an oxide film, a nitride film, an oxynitride film, or the like can be used.
이어서, 도2c와 같이 상기 절연막스페이서(14) 측벽에 스페이서 형상의 반사층(15)을 형성한다. 반사층(15)은 실리콘(Si)층, 티타늄(Ti)층, 티타늄나이트라이드(TiN), 알루미늄(Al)층, 구리(Cu)층 및 텅스텐(W)층 등 광에 대해 고반사율을 갖는 박막은 모두 적용될 수 있다.Subsequently, a spacer-shaped reflective layer 15 is formed on the sidewalls of the insulating film spacer 14 as shown in FIG. 2C. The reflective layer 15 is a thin film having high reflectivity for light such as a silicon (Si) layer, a titanium (Ti) layer, a titanium nitride (TiN), an aluminum (Al) layer, a copper (Cu) layer, and a tungsten (W) layer. Are all applicable.
이어서, 도2d에 도시된 바와 같이, 레지스트 또는 산화막 또는 질화막계열의 절연막(16)을 증착하여 기판을 평탄화시킨 다음, 이 절연막(16) 위에 칼라필터(10)를 어레이한다. 물론 칼라필터는 흑백 이미지센서일 경우 필요가 없을 것이다. 이어서, 칼라필터(10) 상에 평탄화 및 초점거리 조절을 위한 버퍼층(11)을 형성하고 그 위로 마이크로렌즈(12)를 형성한다. 버퍼층(11)으로는 레지스트 또는 산화막 또는 질화막계열의 절연막이 사용될 수 있다.Subsequently, as shown in FIG. 2D, the insulating film 16 of resist or oxide film or nitride film series is deposited to planarize the substrate, and then the color filter 10 is arrayed on the insulating film 16. FIG. Of course, the color filter would not need to be a monochrome image sensor. Subsequently, a buffer layer 11 for planarization and focal length adjustment is formed on the color filter 10, and a microlens 12 is formed thereon. As the buffer layer 11, a resist, an oxide film, or an insulating film of a nitride film series may be used.
결국, 도2d를 참조하면, 본 실시예에 따른 이미지센서는 포토다이오드 상부에서 다층의 절연층이 식각된 후 다시 하나의 절연층 또는 포토레지스트가 형성되므로, 마이크로렌즈를 통과한 후 입사되는 빛의 반사 및 흡수를 감소시킬 수 있고, 아울러 빛 입사 경로에 반사층이 형성되어 있으므로 다소 경사진 빛이 입사되어도 그 빛이 일단 반사층과 만나게 되면 포토다이오드 쪽으로 집광되기 때문에 집광효율을 높일 수 있다. 즉 본 발명에 따른 이미지센서는 광손실 및 집광효율을 극대화시키므로 광감도를 크게 개선할 수 있다.As a result, referring to FIG. 2D, in the image sensor according to the present exemplary embodiment, since an insulating layer or photoresist is formed after the multilayer insulating layer is etched on the photodiode, the incident light after passing through the microlens Since reflection and absorption can be reduced, and a reflective layer is formed in the light incident path, even when slightly inclined light is incident, the light is focused toward the photodiode once the light meets the reflective layer, thereby increasing the light collecting efficiency. That is, the image sensor according to the present invention can greatly improve the light sensitivity because it maximizes the light loss and condensing efficiency.
도3a 및 도3b는 본 발명의 다른 실시예에 따른 이미지센서 제조 공정도이다.3A and 3B are diagrams illustrating a process of manufacturing an image sensor according to another exemplary embodiment of the present invention.
도3a는 도2a의 상태에서 칼라필터를 상기 홈(13) 내에 매립한 것을 보여준다. 즉, 본 실시예에서는 별도로 절연막을 형성하지 않고 상기 홈 내에 직접 칼라필터(10)를 매립하여 평탄화한 후, 도3b와 같이 버퍼층(11)을 형성하고 그 위로 마이크로렌즈(12)를 형성한다.FIG. 3A shows the color filter embedded in the groove 13 in the state of FIG. 2A. In other words, in the present embodiment, the color filter 10 is buried and planarized directly in the groove without forming an insulating film, and then the buffer layer 11 is formed as shown in FIG. 3B and the microlens 12 is formed thereon.
상기 실시예들에서는 광감지소자 즉 수광소자를 포토다이오드로 하여 본 발명을 설명하였으나 포토다이오드 대신에 포토게이트 등 다른 광감지소자를 적용하는 이미지센서에도 본 발명은 적용되는 등, 본 발명의 기술 사상은 상기 바람직한 실시예에 따라 구체적으로 기술되었으나, 상기한 실시예는 그 설명을 위한 것이며 그 제한을 위한 것이 아님을 주의하여야 한다. 또한, 본 발명의 기술 분야의 통상의 전문가라면 본 발명의 기술 사상의 범위내에서 다양한 실시예가 가능함을 이해할 수 있을 것이다.In the above embodiments, the present invention has been described using a photosensitive device, that is, a light receiving device as a photodiode, but the present invention is also applied to an image sensor that applies another photosensitive device such as a photogate instead of a photodiode. Although specifically described in accordance with the preferred embodiment above, it should be noted that the above embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention.
상술한 바와 같이, 본 발명에 따른 이미지센서는 광 손실 및 광집속력이 증대되어 광감도를 개선하므로 이미지센서의 성능 및 신뢰성을 크게 향상시키는 탁월한 효과가 있다.As described above, the image sensor according to the present invention has an excellent effect of greatly improving the performance and reliability of the image sensor because the light loss and light focusing power is increased to improve the light sensitivity.
Claims (11)
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6861686B2 (en) | 2003-01-16 | 2005-03-01 | Samsung Electronics Co., Ltd. | Structure of a CMOS image sensor and method for fabricating the same |
| KR100731130B1 (en) * | 2005-12-29 | 2007-06-22 | 동부일렉트로닉스 주식회사 | Cmos image sensor and method for manufacturing the same |
| US7390686B2 (en) | 2004-12-30 | 2008-06-24 | Dongbu Electronics Co., Ltd | CMOS image sensor and method for fabricating the same |
| US7400003B2 (en) | 2003-01-16 | 2008-07-15 | Samsung Electronics Co., Ltd. | Structure of a CMOS image sensor and method for fabricating the same |
| KR100906558B1 (en) * | 2007-11-05 | 2009-07-07 | 주식회사 동부하이텍 | Image Sensor and Method for Manufacturing Thereof |
| KR100974618B1 (en) * | 2008-02-29 | 2010-08-06 | 인제대학교 산학협력단 | Image Sensor with improved photo sensitivity |
-
1999
- 1999-12-30 KR KR1019990066708A patent/KR20010059316A/en not_active Application Discontinuation
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6861686B2 (en) | 2003-01-16 | 2005-03-01 | Samsung Electronics Co., Ltd. | Structure of a CMOS image sensor and method for fabricating the same |
| US7400003B2 (en) | 2003-01-16 | 2008-07-15 | Samsung Electronics Co., Ltd. | Structure of a CMOS image sensor and method for fabricating the same |
| US7462507B2 (en) | 2003-01-16 | 2008-12-09 | Samsung Electronics Co., Ltd. | Structure of a CMOS image sensor and method for fabricating the same |
| US7390686B2 (en) | 2004-12-30 | 2008-06-24 | Dongbu Electronics Co., Ltd | CMOS image sensor and method for fabricating the same |
| US7642613B2 (en) | 2004-12-30 | 2010-01-05 | Dongbu Electronics, Inc. | CMOS image sensor and method for fabricating the same |
| KR100731130B1 (en) * | 2005-12-29 | 2007-06-22 | 동부일렉트로닉스 주식회사 | Cmos image sensor and method for manufacturing the same |
| KR100906558B1 (en) * | 2007-11-05 | 2009-07-07 | 주식회사 동부하이텍 | Image Sensor and Method for Manufacturing Thereof |
| KR100974618B1 (en) * | 2008-02-29 | 2010-08-06 | 인제대학교 산학협력단 | Image Sensor with improved photo sensitivity |
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