近日，Optics Letters, Vol. 32, 2096 (2007) 發(fā)表了微電子研究所的最新研究成果“Edge-View Photodetector for Optical Interconnects”。該成果發(fā)表后，很快被Nature Photonics，Vol. 1, November 2007在Research Highlights中作為頭條重點(diǎn)介紹，內(nèi)容如下： Ease of fabrication and alignment are important issues when designing integrated optical circuits. Scientists from the Chinese Academy of Sciences and the Georgia Institute of Technology have now demonstrated a clever and cost-effective approach for manufacturing photodetectors. By using a combined process of anisotropic liquid etching, chemical-vapour deposition and lithography, Zhihua Li and co-workers have fabricated an edge-view photodetector. In their approach, light in a waveguide is directly incident on a photodetecting area positioned on the sloped side of a mesa. This ensures alignment of the waveguide and the photodetector without the need for mirrors and lenses. The performance of the device — a responsivity of 0.13 A/W at a wavelength of 850 nm — is still in need of improvement. However, the researchers expect to achieve this with better semiconductor layer growth and enhanced matching of the waveguide cross-section and photodetecting area..

　　譯文：簡(jiǎn)便的制作和對(duì)準(zhǔn)方法對(duì)光電集成電路來說是十分重要的。中國科學(xué)院和喬治亞理工學(xué)院的科學(xué)家們展示了精巧的光電探測(cè)器制作方法以降低光電集成成本。通過各向異性化學(xué)腐蝕、晶體材料外延生長和光刻等工藝過程，李志華以及他的同事研制了斜面受光探測(cè)器（EVPD）。按照他們的方法，通過光波導(dǎo)傳播的光可以直接入射至臺(tái)階結(jié)構(gòu)的斜面受光區(qū)上，實(shí)現(xiàn)光波導(dǎo)和光電探測(cè)器之間的耦合對(duì)準(zhǔn)，無需使用反射鏡和微透鏡。該探測(cè)器的性能——對(duì)850nm光的響應(yīng)度為0.13A/W——還需要提高。研究者們希望通過優(yōu)化半導(dǎo)體材料的外延生長，并使光波導(dǎo)截面和受光區(qū)更好地匹配來提高探測(cè)器的效率。

　　目前，制約芯片間光互連廣泛應(yīng)用的主要因素之一是技術(shù)成本太高。雖然光電器件及其陣列已發(fā)展成熟并商用化，但是要組成光鏈路并實(shí)用化則仍需克服較大的成本障礙。目前主流的光電器件VCSEL和PIN PD都是平面出光和受光，而芯片間的光互連傳輸方向也在平面上，所以要完成光波與光電器件的耦合就需要光路在耦合前轉(zhuǎn)折90°，這通常都是通過45°反射鏡和微透鏡來實(shí)現(xiàn)光路的轉(zhuǎn)折與耦合對(duì)準(zhǔn)。反射鏡和微透鏡的組裝及繁瑣的光對(duì)準(zhǔn)工序是產(chǎn)生光互連成本的重要部分。EVPD可免去光接收端反射鏡和微透鏡的使用，對(duì)簡(jiǎn)化芯片間光互連結(jié)構(gòu)，降低成本，促進(jìn)芯片間光互連技術(shù)的實(shí)用化具有重要意義。