<p>新聞：光電子</p>
<p>連續波鋁鎵氮紫外 A 激光二極管</p>
<p>美國俄亥俄州立大學宣稱首次演示了通過等離子體輔助分子束外延（PAMBE）單體生長的連續波（CW）電泵鋁鎵氮（AlGaN）紫外 A（UV-A，315–400nm）激光二極管 [Arnob Ghosh 等，光波技術雜誌，2026 年 1 月 14 日在線發表]。</p>
<p>紫外激光二極管和 LED 正在為廣泛的潛在應用進行開發：空氣和水的淨化、消毒、滅菌、基於熒光的生物檢測、微加工以及各種生物技術過程。光電子紫外光源具有許多與緊湊尺寸、相對較高的能量效率和降低的製造成本相關的優勢。應用更傾向於使用連續波而非脈衝模式操作。</p>
<p>研究人員評論道：“值得注意的是，大多數先前報告的結果是在脈衝條件下獲得的，而這項工作是在連續波操作下進行的，代表了更嚴格和實際相關的操作條件。”</p>
<p>鋁鎵氮合金半導體材料的一個主要缺點是實現孔注入的困難，因為傳統的鎂摻雜具有低載流子濃度效率。俄亥俄州立大學的設備使用了透明的埋藏隧道結（TJ），使孔能夠注入到量子阱活性區域，儘管頂部包層由 n 型 AlGaN 組成。</p>
<p>團隊解釋道：“該設備結構具有透明的同質結隧道結，以增強孔注入，同時採用窄脊、指數引導的非對稱波導設計，顯著改善光學約束，同時最小化來自基板的吸收損失。”</p>
<p>研究人員計劃在未來的工作中優化設計和在低位錯、高鋁含量的 AlGaN 或 AlN 基板上生長，以將發射擴展到更短波長，甚至更具挑戰性的 UV-B（280–315nm）和 UV-C（100–280nm）光譜區域。</p>
<p><img src="https://imageproxy.pbkrs.com/https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f1.jpg?x-oss-process=image/auto-orient,1/interlace,1/resize,w_1440,h_1440/quality,q_95/format,jpg" alt="" original-src="https://imageproxy.pbkrs.com/https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f1.jpg"/></p>
<p><em>圖 1：（a）設計的平面 UV-A AlGaN 激光結構的橫截面示意圖，以及（b）熱平衡下的相應能帶圖。</em></p>
<p>激光二極管的外延材料是在 c 面自由立方氮化鎵基板上生長的（圖 1）。該結構包括一個電子阻擋層（EBL），以抑制來自活性區域的電子溢出。用於孔注入到多個量子阱（MQWs）的隧道結由薄的重摻雜 p++-型和 n++-型 AlGaN 層組成。</p>
<p>層厚度經過精心設計，以確保在 MQW 處具有高光學約束因子。特別是，設計了一個厚的底部包層，以補償 n-GaN 基板的相對較高折射率，否則會傾向於將光學模式向下拉，從而導致基板中寄生吸收的增加。波導厚度也是考慮到這一點而選擇的。</p>
<p>研究人員評論道：“這種配置有效地將光場引導遠離損耗較大的 GaN 基板，並改善與量子阱的模式重疊。”</p>
<p>材料被製造成 3μm 寬的脊波導激光器。切割的腔長為 500μm。脊通過感應耦合等離子體反應離子刻蝕（ICP-RIE）刻蝕至 420nm 的深度。脊的設計旨在增強量子阱區域光場的橫向約束。</p>
<p>歐姆型頂側接觸施加在 n-AlGaN 包層上，由退火的鈦/鋁/鎳/金組成。</p>
<p>激光器還通過等離子體增強化學氣相沉積（PECVD）二氧化硅進行了鈍化。底部接觸金屬與頂部相同，在將設備薄化至 140μm 後施加。還形成了鎳/金接觸墊。表徵測試是在沒有光學塗層的未封裝設備上進行的。</p>
<p>激光器在連續波操作下，在 8.5V 正向偏置下達到了 6kA/cm2 的閾值電流密度（Jth）（圖 2）。總的外部微分量子效率（DEQE，ηd）為 11%。</p>
<p><img src="https://imageproxy.pbkrs.com/https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f2.jpg?x-oss-process=image/auto-orient,1/interlace,1/resize,w_1440,h_1440/quality,q_95/format,jpg" alt="" original-src="https://imageproxy.pbkrs.com/https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f2.jpg"/></p>
<p><em>圖 2：（a）法布里 - 佩羅激光器的光輸出功率 - 電流 - 電壓（L-I-V）特性，以及（b）閾值以下和以上的發射光譜，發射輪廓插圖。光譜儀分辨率帶寬（RBW）為 0.38nm。</em></p>
<p>團隊評論道：“預計通過在光學面上加入介電鏡面塗層和通過封裝進行適當的熱管理，ηd 將顯著改善。”</p>
<p>亞閾值（85mA）峯值波長為 361nm，半高全寬（FWHM）為 8nm。閾值以上（150mA），波長為 360.3nm（0.5nm FWHM，接近分辨率極限）。</p>
<p><img src="https://imageproxy.pbkrs.com/https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f3.jpg?x-oss-process=image/auto-orient,1/interlace,1/resize,w_1440,h_1440/quality,q_95/format,jpg" alt="" original-src="https://imageproxy.pbkrs.com/https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f3.jpg"/></p>
<p><em>圖 3：所呈現的 CW 設備與其他報告的脈衝模式 UV-A 激光二極管的（a）閾值電流密度，（b）工作電壓和（c）ηd 的基準比較。</em></p>
<p>研究人員將他們的 CW UV-A 激光二極管的性能與工程文獻中脈衝模式性能的報告進行了比較（圖 3）：“數據清楚地表明，這項工作實現了創紀錄的低閾值電壓和電流密度，主要歸因於同質結 TJ 的實施和改進的腔體設計。”</p>
<p>鋁鎵氮紫外 A 激光二極管鋁鎵氮 PECVD 氮化鎵基板</p>
<p>https://doi.org/10.1109/JLT.2026.3654012</p>
<p><em>作者 Mike Cooke 是一名自由技術記者，自 1997 年以來一直在半導體和先進技術領域工作。</em></p>

<p>俄亥俄州立大學展示了首個連續波（CW）AlGaN UV-A 激光二極管，採用等離子體輔助分子束外延技術。這一進展使其在空氣和水淨化、消毒以及生物技術等領域的應用成為可能。該設備具有透明的埋藏隧道結，以改善孔注入，並且設計上增強了光學限制。CW 操作在 8.5V 下實現了 6kA/cm² 的閾值電流密度，總的外部量子效率為 11%。未來的工作旨在優化設計以實現更短波長的紫外線</p>

<p>News: Optoelectronics</p>
<div class="lb-trans"><p>新聞：光電子</p>
</div><p>Continuous-wave AlGaN UV-A laser diode</p>
<div class="lb-trans"><p>連續波鋁鎵氮紫外 A 激光二極管</p>
</div><p>Ohio State University in the USA has claimed the first demonstration of continuous-wave (CW), electrically pumped aluminium gallium nitride (AlGaN) ultraviolet-A (UV-A, 315–400nm) laser diodes grown monolithically by plasma-assisted molecular beam epitaxy (PAMBE) [Arnob Ghosh et al, Journal of Lightwave Technology, published online 14 January 2026].</p>
<div class="lb-trans"><p>美國俄亥俄州立大學宣稱首次演示了通過等離子體輔助分子束外延（PAMBE）單體生長的連續波（CW）電泵鋁鎵氮（AlGaN）紫外 A（UV-A，315–400nm）激光二極管 [Arnob Ghosh 等，光波技術雜誌，2026 年 1 月 14 日在線發表]。</p>
</div><p>UV laser diodes and LEDs are being developed for a wide range of potential deployments: air and water purification, disinfection, sterilization, fluorescence-based biological detection, microfabrication, and various biotechnology processes. Optoelectronic UV sources offer many advantages related to compact size, relatively high energy efficiency, and reduced manufacturing cost. The applications prefer CW over pulsed-mode operation.</p>
<div class="lb-trans"><p>紫外激光二極管和 LED 正在為廣泛的潛在應用進行開發：空氣和水的淨化、消毒、滅菌、基於熒光的生物檢測、微加工以及各種生物技術過程。光電子紫外光源具有許多與緊湊尺寸、相對較高的能量效率和降低的製造成本相關的優勢。應用更傾向於使用連續波而非脈衝模式操作。</p>
</div><p>The researchers comment: “It is worth noting that most of the previously reported results were obtained under pulsed conditions, whereas this work was performed under CW operation, representing more stringent and practically relevant operating conditions.”</p>
<div class="lb-trans"><p>研究人員評論道：“值得注意的是，大多數先前報告的結果是在脈衝條件下獲得的，而這項工作是在連續波操作下進行的，代表了更嚴格和實際相關的操作條件。”</p>
</div><p>A leading disadvantage of AlGaN alloy semiconductor material is the difficulty in achieving hole injection, since conventional p-doping with magnesium has low carrier concentration efficiency. The OSU device used a transparent buried tunnel junction (TJ) enabling hole injection into the quantum-well active region, despite the top cladding being composed of n-type AlGaN.</p>
<div class="lb-trans"><p>鋁鎵氮合金半導體材料的一個主要缺點是實現孔注入的困難，因為傳統的鎂摻雜具有低載流子濃度效率。俄亥俄州立大學的設備使用了透明的埋藏隧道結（TJ），使孔能夠注入到量子阱活性區域，儘管頂部包層由 n 型 AlGaN 組成。</p>
</div><p>The team explains: “The device structure features a transparent homojunction tunnel junction to enhance hole injection, along with a narrow-ridge, index-guided asymmetric waveguide design that significantly improves optical confinement while minimizing absorption losses from the substrate.”</p>
<div class="lb-trans"><p>團隊解釋道：“該設備結構具有透明的同質結隧道結，以增強孔注入，同時採用窄脊、指數引導的非對稱波導設計，顯著改善光學約束，同時最小化來自基板的吸收損失。”</p>
</div><p>The researchers plan in future work to optimize design and growth on low-dislocation, high-Al-content AlGaN or AlN substrates to extend emission into the shorter-wavelength, and even more challenging, UV-B (280–315nm) and UV-C (100–280nm) spectral regions.</p>
<div class="lb-trans"><p>研究人員計劃在未來的工作中優化設計和在低位錯、高鋁含量的 AlGaN 或 AlN 基板上生長，以將發射擴展到更短波長，甚至更具挑戰性的 UV-B（280–315nm）和 UV-C（100–280nm）光譜區域。</p>
</div><p><img src="https://imageproxy.pbkrs.com/https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f1.jpg" alt="" original-src="https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f1.jpg"/></p>
<p><em>Figure 1: (a) Cross-sectional schematic of designed planar UV-A AlGaN laser structure, and (b) corresponding energy-band diagram in thermal equilibrium.</em></p>
<div class="lb-trans"><p><em>圖 1：（a）設計的平面 UV-A AlGaN 激光結構的橫截面示意圖，以及（b）熱平衡下的相應能帶圖。</em></p>
</div><p>The epitaxial material for the laser diode was grown on c-plane free-standing GaN substrates (Figure 1). The structure included an electron-blocking layer (EBL) to suppress electron overflow from the active region. The tunnel junction for hole injection into the multiple quantum wells (MQWs) consisted of thin heavily doped layers of p++- and n++-type AlGaN.</p>
<div class="lb-trans"><p>激光二極管的外延材料是在 c 面自由立方氮化鎵基板上生長的（圖 1）。該結構包括一個電子阻擋層（EBL），以抑制來自活性區域的電子溢出。用於孔注入到多個量子阱（MQWs）的隧道結由薄的重摻雜 p++-型和 n++-型 AlGaN 層組成。</p>
</div><p>The layer thicknesses were carefully designed to ensure a high optical confinement factor at the MQW. In particular, a thick bottom cladding was designed to compensate for the relatively high refractive index of the n-GaN substrate, which otherwise would tend to pull the optical mode downward, resulting in increased parasitic absorption in the substrate. The waveguide thicknesses were also chosen with this in mind.</p>
<div class="lb-trans"><p>層厚度經過精心設計，以確保在 MQW 處具有高光學約束因子。特別是，設計了一個厚的底部包層，以補償 n-GaN 基板的相對較高折射率，否則會傾向於將光學模式向下拉，從而導致基板中寄生吸收的增加。波導厚度也是考慮到這一點而選擇的。</p>
</div><p>The researchers comment: “This configuration effectively redirects the optical field away from the lossy GaN substrate and improves mode overlap with the QWs.”</p>
<div class="lb-trans"><p>研究人員評論道：“這種配置有效地將光場引導遠離損耗較大的 GaN 基板，並改善與量子阱的模式重疊。”</p>
</div><p>The material was fabricated into 3μm-wide ridge waveguide lasers. The cleaved cavity length was 500μm. The ridge was formed by inductively coupled plasma reactive-ion etching (ICP-RIE) to a depth of 420nm. The ridge was designed to enhance lateral confinement of the optical field in the QW region.</p>
<div class="lb-trans"><p>材料被製造成 3μm 寬的脊波導激光器。切割的腔長為 500μm。脊通過感應耦合等離子體反應離子刻蝕（ICP-RIE）刻蝕至 420nm 的深度。脊的設計旨在增強量子阱區域光場的橫向約束。</p>
</div><p>The ohmic top-side contacts were applied to the n-AlGaN cladding, consisting of annealed titanium/aluminium/nickel/gold.</p>
<div class="lb-trans"><p>歐姆型頂側接觸施加在 n-AlGaN 包層上，由退火的鈦/鋁/鎳/金組成。</p>
</div><p>The lasers were also passivated with plasma-enhanced chemical vapor deposition (PECVD) silicon dioxide. The bottom contact metals were the same as for the top side, applied after thinning the device to 140μm. Nickel/gold contact pads were also formed. The characterization tests were on unpackaged devices without optical coatings of the facets.</p>
<div class="lb-trans"><p>激光器還通過等離子體增強化學氣相沉積（PECVD）二氧化硅進行了鈍化。底部接觸金屬與頂部相同，在將設備薄化至 140μm 後施加。還形成了鎳/金接觸墊。表徵測試是在沒有光學塗層的未封裝設備上進行的。</p>
</div><p>The lasers, in CW operation, achieved 6kA/cm2 threshold current density (Jth) at 8.5V forward bias (Figure 2). The total differential external quantum efficiency (DEQE, ηd) was 11%.</p>
<div class="lb-trans"><p>激光器在連續波操作下，在 8.5V 正向偏置下達到了 6kA/cm2 的閾值電流密度（Jth）（圖 2）。總的外部微分量子效率（DEQE，ηd）為 11%。</p>
</div><p><img src="https://imageproxy.pbkrs.com/https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f2.jpg" alt="" original-src="https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f2.jpg"/></p>
<p><em>Figure 2: (a) Light output power–current–voltage (L-I-V) characteristics of Fabry–Pérot laser, and (b) emission spectra at below- and above-threshold with emission profile inset. Spectrometer resolution bandwidth (RBW) was 0.38nm.</em></p>
<div class="lb-trans"><p><em>圖 2：（a）法布里 - 佩羅激光器的光輸出功率 - 電流 - 電壓（L-I-V）特性，以及（b）閾值以下和以上的發射光譜，發射輪廓插圖。光譜儀分辨率帶寬（RBW）為 0.38nm。</em></p>
</div><p>The team comments: “The ηd is expected to improve significantly with the incorporation of dielectric mirror coating on the facets and proper thermal management via packaging.”</p>
<div class="lb-trans"><p>團隊評論道：“預計通過在光學面上加入介電鏡面塗層和通過封裝進行適當的熱管理，ηd 將顯著改善。”</p>
</div><p>The subthreshold (85mA) peak wavelength was 361nm with 8nm full-width at half maximum (FWHM). Above threshold (150mA), the wavelength was 360.3nm (0.5nm FWHM, close to resolution limit).</p>
<div class="lb-trans"><p>亞閾值（85mA）峯值波長為 361nm，半高全寬（FWHM）為 8nm。閾值以上（150mA），波長為 360.3nm（0.5nm FWHM，接近分辨率極限）。</p>
</div><p><img src="https://imageproxy.pbkrs.com/https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f3.jpg" alt="" original-src="https://semiconductor-today.com/news_items/2026/feb/26012_ohiostate_f3.jpg"/></p>
<p><em>Figure 3: Benchmark comparisons of (a) threshold current density, (b) operating voltage and (c) ηd of presented CW device with other reported UV-A laser diodes under pulsed-mode operation.</em></p>
<div class="lb-trans"><p><em>圖 3：所呈現的 CW 設備與其他報告的脈衝模式 UV-A 激光二極管的（a）閾值電流密度，（b）工作電壓和（c）ηd 的基準比較。</em></p>
</div><p>The researchers compared the performance of their CW UV-A laser diode with reports of pulse-mode performance in the engineering literature (Figure 3): “The data clearly demonstrate that this work achieved a record low threshold voltage and current density, primarily attributed to the implementation of a homojunction TJ and an improved cavity design.”</p>
<div class="lb-trans"><p>研究人員將他們的 CW UV-A 激光二極管的性能與工程文獻中脈衝模式性能的報告進行了比較（圖 3）：“數據清楚地表明，這項工作實現了創紀錄的低閾值電壓和電流密度，主要歸因於同質結 TJ 的實施和改進的腔體設計。”</p>
</div><p>AlGaN UV-A laser diode AlGaN PECVD GaN substrate</p>
<div class="lb-trans"><p>鋁鎵氮紫外 A 激光二極管鋁鎵氮 PECVD 氮化鎵基板</p>
</div><p>https://doi.org/10.1109/JLT.2026.3654012</p>
<div class="lb-trans"><p>https://doi.org/10.1109/JLT.2026.3654012</p>
</div><p><em>The author Mike Cooke is a freelance technology journalist who has worked in the semiconductor and advanced technology sectors since 1997.</em></p>
<div class="lb-trans"><p><em>作者 Mike Cooke 是一名自由技術記者，自 1997 年以來一直在半導體和先進技術領域工作。</em></p>
</div>

連續波 AlGaN 紫外 A 類激光二極管