Abstract:
PURPOSE: An anti-guide type surface emitting laser and a method for manufacturing the same are provided to realize a high power with a low current at a single mode since the output light is small in size and it scarcely diverges, thereby reducing the manufacturing cost thereof. CONSTITUTION: An anti-guide type surface emitting laser includes a lower Bragg mirror layer(102), a resonance layer(103), a beam width control layer(113) and an upper Bragg mirror layer(109). The beam width control layer(113) formed on top of the resonance layer(103) includes a first thin film(104) defining the central portion as a current injection region, a second thin film layer(105) for generating an effective refraction index difference between the peripheral portion and the central portion and a third thin film(107) formed between the first thin film(104) and the second thin film(105). The lower Bragg mirror layer(102) is formed on a semiconductor substrate and the resonance layer(103) is formed on top of the lower Bragg mirror layer(102). The upper Bragg mirror layer(109) formed on top of the beam width control layer(113) has a step at a boundary between the edge portion and the central portion by the second thin film(105).
Abstract:
본 발명은 반도체 반사경 또는 광학 필터로 이용될 수 있는 반도체 광소자의 제작 방법에 대해 개시한다. 에칭비가 서로 다른 두가지 이상의 반도체층들을 교대로 적층한 후 적어도 한 종류의 반도체층들을 선택적으로 에칭하여 에어갭(air gap)을 형성하고, 에어갭이 매립되도록 열전달 특성이 양호한 산화물 혹은 질화물을 증착한다. 에어갭에 매립된 산화물 혹은 질화물과 반도체층의 큰 굴절률 차이로 인하여 적은 주기로도 효과적으로 높은 반사율을 갖는 반도체 반사경 또는 광학 필터를 구현할 수 있다.
Abstract:
본 발명은 1.3 ~ 1.55 ㎛ 대역의 장파장 수직 공진 표면방출 레이저 및 그 제작방법에 관한 것이다. 종래 수직 공진 표면방출 레이저의 전류 감금 구조를 형성하기 위해 취해진 여러 방법은 장파장 수직 공진 표면방출 레이저 제작방법으로 적용하기에는 문제가 있다. 본 발명에서는 전류 감금 구조와 그 형성방법을 개선하여 장파장 수직 공진 표면방출 레이저 및 그 제작방법을 제공하는 것을 목적으로 한다. 이 목적을 달성하기 위하여, 본 발명에서는 가벼운 이온의 저에너지 주입과 터널 접합층의 복합적 사용을 통한 새로운 전류 감금 구조를 제시한다. 저에너지 이온주입은 표면 가까이에 저항이 큰 층을 형성할 수 있어서, 기존의 고에너지 이온주입과 달리 최소 전류 주입 직경을 아주 작게 만들 수 있고 소자의 저항을 크게 줄일 수 있어 열 발생을 감소시킨다. 터널 접합층의 사용으로, 전하 운반자에 의한 광손실 저항을 줄여주므로 효과적으로 소자의 전기적 특성을 향상시킨다.
Abstract:
PURPOSE: A laser device incorporating thereinto an astigmatic micro-lens is provided to correct a difference between cutoff angles due to an asymmetric of a laser mode. CONSTITUTION: A laser device incorporating thereinto an astigmatic micro-lens includes a distributed Bragg mirror(13) formed on a top surface of a substrate(10), an active medium(12) formed on a top surface of the distributed Bragg mirror(13), a mirror(11) formed in such a way that the mirror(11) is inclined at a predetermined angle with coexisting in the same plane of the active medium(12) and an astigmatic micro lens(14) formed on a bottom surface of the substrate(10). In the laser device, the astigmatic micro-lens is used to correct a difference between the angles of radiation of a light beam radiated from the bottom surface of the substrate(10) through the distributed Bragg mirror(13).
Abstract:
PURPOSE: A long wavelength surface emitting laser device having a diffusion area on both end parts of an upper mirror layer and a method for fabricating the same are provided to prevent a loss of absorption of a p type doping layer within a resonator and reduce a scattering loss of a mirror layer and a carrier loss by controlling efficiently current flow. CONSTITUTION: A lower mirror layer(22) is formed on an n type InP semiconductor substrate(21). An active layer(23) is formed on the lower mirror layer(22). The active layer(23) is formed with a quantum well layer and a spatial layer. An electron leakage barrier(24) is formed on the active layer(23). A current induction layer(25) is formed on the electron leakage barrier(24). A current expansion layer(26) is formed on the current induction layer(25). The current expansion layer(26) is formed by a p type semiconductor layer. An upper mirror layer(27) is formed on the current expansion layer(26). A Zn diffusion layer(28) is formed on end parts of the upper mirror layer(27). An insulating layer(29) is used for forming an air layer among the current expansion layer(26), the current induction layer(25), and the current leakage barrier(24). The first metallic line(31) is connected with the upper mirror layer(27). The second metallic line(32) is connected with a back side of the n type InP semiconductor substrate(21).
Abstract:
A long-wavelength VCSEL is provided. The laser includes a first conductive semiconductor substrate, lower mirror layers that are formed on the semiconductor substrate and are proper to the Bregg-reflection, an active layer formed on the lower mirror layer, a current passage layer that is formed on the active layer as a path through which an electric current flows into the active layer, current blocking layers that are formed on the active layer to encompass the current passage layer and limit the path through which an electric current flows into the active layer, an intra-cavity contact layer formed on a portion of the current passage layer and the current blocking layer, upper mirror layers that are formed on a portion of the intra-cavity contact layer and are proper to the Bragg-reflection, a first electrode formed on the exposed surface of the intra-cavity contact layer and the upper mirror layers, and a second electrode formed on a predetermined surface of the semiconductor substrate
Abstract:
A folded cavity laser for generating a laser beam, includes a substrate provided with a distributed Bragg reflector (DBR); an active medium formed above the DBR for amplifying the laser beam; a first and a second mirrors formed on sides of the active medium, respectively, for making a horizontal cavity and for reflecting the amplified laser beam to the DBR; and a microlens, formed on the substrate opposite the DBR, for making the amplified laser beam astigmatic after passing therethrough.
Abstract:
PURPOSE: A multi-channel long wavelength VCSEL array and a fabricating method thereof are provided to form constantly an interval of a laser oscillation wavelength by controlling a resonant interval. CONSTITUTION: A multi-channel long wavelength VCSEL array includes a semiconductor substrate(10), a bottom mirror(20), an active region(30), a current limit layer(40), a superlattice control layer(50), and a top mirror(60). The bottom mirror is formed on the semiconductor substrate. The active region is formed on the bottom mirror. The current limit layer is formed on the active region in order to limit efficiently the current and enhance the efficiency of the heat transfer. The superlattice control layer is formed on the current limit layer in order to control an interval of laser oscillation wavelength. The top mirror is formed on the superlattice control layer.
Abstract:
PURPOSE: A method for fabricating a long wavelength VCSEL(Vertical-Cavity Surface-Emitting Laser) is provided to reduce a current implantation diameter by implanting heavy ions and regrowing a crystal. CONSTITUTION: A lower dispersion Bragg reflection mirror(10), a laser active medium(11), and a heat spreading layer(12) are sequentially grown by considering the thickness of a resonator. A photoresist mask is formed on the heat spreading layer. A current confining layer(13) is formed by implanting ions into an exposed portion of the heat spreading layer. The photoresist mask is removed. An Inp layer(14) and a current spreading layer(15) are formed regrown on the heat spreading layer. An electrode(16) is formed on the current spreading layer. An upper dispersion Bragg reflection mirror(17) is formed thereon. An Au reflective mirror(18) is formed on the upper dispersion Bragg reflection mirror.
Abstract:
본 발명은 통신용 다채널 광원으로서 성능을 갖춘 장파장 대역의 표면방출형 레이저 및 그것의 제조방법에 관한 것으로 보다 상세하게는 활성층 상에 두꺼운 내부공진접촉층을 가지는 메사구조 및 이온주입층을 형성하므로써 효과적인 전류주입 및 열분산을 달성할 수 있는 두꺼운 내부공진접촉층을 갖는 장파장 표면방출 레이저 및 그것의 제조방법에 관한 것이다. 상기 메사 구조 및 상기 이온주입층에 의하여 전류가 상기 내부공진접촉층 상의 전극으로부터 상기 내부공진접촉층을 통과하여 상기 메사 구조의 하부에 있는 활성층으로 도달하는 전류유도구경이 형성된다. 이와 함께, 상기 활성층에서 발행한 열은 상기 전류유도구경에 의하여 흐르는 전류와 반대방향으로 상기 내부공진접촉층을 통과하여 그것 상에 형성된 전극을 통하여 배출된다.