Focused Ion Beam Fabrication of Optical Storage Structures Using Biphotonic Stimulation in Rare-Earth Doped Materials

ECS-9906984 Steckl这份提交给NSF的提案讨论了一种高密度归档光学存储器结构，该结构使用来自稀土掺杂半导体（如GaN）和绝缘体（特别是重金属氟化物玻璃，如ZBLAN）的双光子上转换光电发射。我们计划利用聚焦离子束（FIB）技术的手段密集“写”的内存与本地包的稀土（RE）物种。我们将使用两个不同光子能量的激光器，通过两步、两能量上转换过程对某些稀土离子（如Pr、Er、Tm）进行选择性的数据“阅读”。我们已经获得了我们所提出的方法的关键组成部分的初步结果：（1）用于RE注入的FIB源的制造;（2）Pr到GaN中的FIB注入和强光电发射的证据;（3）ZBLAN中微腔的FIB铣削;（4）ZBLAN的双光子发射;（5）单片集成的基于CMOS的光电探测器的制造和表征;接收器阵列，其提供可调谐光功率阈值并且对低功率光信号高度敏感。此外，我们已经构建了一个光存储介质的表征系统，使我们能够评估的可行性的RE掺杂的样品产生的光存储应用。除了允许在各种光学激发方案下对RE掺杂样品进行目视检查外，我们开发的表征系统还提供了对单个/多个数据位进行光学表征（光谱和光功率测量）的能力。最后，该表征系统将CMOS光接收器阵列集成到一个伪读取头组件中，该组件允许对RE掺杂的光存储介质进行面向位、面向字或面向页的阅读。我们的初步结果表明了我们开发的整个光存储器概念的可行性。在这里提出的工作中，我们计划调查的FIB写入过程中获得最大的位存储密度和方法的限制，以获得最高的信噪比在双光子读取操作。为了评估存储器的性能参数（如数据速率，访问时间，误码率，位串扰和页串扰），我们计划设计，制造和表征存储介质和检测结构，包含103位的阵列。

ECS-9906984StecklThis proposal to NSF discusses a high density archival optical memory structure using biphotonic upconversion photoemission from rare-earth-doped semiconductors (such as GaN) and insulators (especially heavy metal fluoride glasses such as ZBLAN). We plan to utilize focused ion beam (FIB) techniques as the means for densely "writing" the memory with localized packets of rare earth (RE) species. We will use two lasers of different photon energy to perform selective "reading" of the data through the two-step, two-energy upconversion process in certain rare earth ions (such as Pr, Er, Tm). We have obtained preliminary results on the critical ingredients of our proposed approach: (1) fabrication of FIB sources for RE implantation; (2) FIB implantation of Pr into GaN and evidence of strong photoemission; (3) FIB milling of microcavities in ZBLAN; (4) biphotonic emission from ZBLAN; (5) fabrication and characterization of a monolithically integrated CMOS based photodetector/receiver array that provides a tunable optical power threshold and is highly sensitive to low power optical signals. Further, we have constructed an optical storage media characterization system that allows us to evaluate the viability of RE-doped samples generated for optical storage applications. In addition to allowing visual inspection of RE doped samples under various optical excitation schemes, the characterization system we have developed provides the capability to perform optical characterization (spectroscopic and optical power measurements) on single/multiple data bits. Finally, the characterization system incorporates the CMOS photoreceiver array into a pseudo read-head assembly that allows for bit-oriented, word-oriented or page-oriented reading of an RE-doped optical storage media.Our preliminary results indicate the feasibility of the overall optical memory concept which we have developed. In the work proposed here, we plan to investigate the limits of the FIB write process for obtaining maximum bit storage density and approaches for obtaining the highest signal-to noise ratio in the biphotonic read operation. To evaluate the memory performance parameters (such as data rate, access time, bit error rate, bit-cross-talk and page-cross-talk), we plan to design, fabricate and characterize storage media and detection structures containing arrays of 103 bits.