Plasma-assisted atomic layer deposition of alumina and Parylene-C bi-layer encaps

氧化铝和聚对二甲苯-C 双层封装的等离子体辅助原子层沉积

• 批准号: 8877517
• 负责人: Rajmohan Bhandari
• 金额: $ 33.41万
• 依托单位: BLACKROCK MICROSYSTEMS
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8877517
• 关键词: Address; Advanced Development; Aluminum Oxide; Architecture; Area; Benchmarking; Body Fluids; Brain; Ceramics; Characteristics; Charge; Chemicals; Chronic; Complex; Custom; Deposition; Development; Devices; Dimensions; Effectiveness; Electrodes; Electronics; Encapsulated; Environment; Extravasation; Failure; Foreign Bodies; Geometry; Gold; Health; Human; Implant; Injection of therapeutic agent; Ions; Lasers; Light; Longevity; Measures; Medical Device; Metals; Methods; Monitor; Neurosciences; Operative Surgical Procedures; Performance; Phase; Plasma; Polymers; Procedures; Process; Production; Property; Protocols documentation; RF coil; Research; Risk; Scheme; Semiconductors; Site; Small Business Innovation Research Grant; Sorting - Cell Movement; Staging; Structure; Surface; System; Techniques; Technology; Testing; Utah; Water; Wireless Technology; Work; atomic layer deposition; biomaterial compatibility; brain machine interface; combat; electric impedance; electrical property; follow-up; implantable device; implantation; improved; in vivo; manufacturing process; microsystems; nervous system disorder; neural stimulation; neuroprosthesis; next generation; novel; parylene; parylene C; relating to nervous system; response; success

DESCRIPTION (provided by applicant): A range of neurological diseases are now being researched or treated using fully implantable electronic systems to either record or modulate brain activity in humans. These implants are currently being protected using polymer coatings that envelop the implant and help keep body fluids away from the sensitive electronics. Brain implants with complex three-dimensional geometries, like the Utah Electrode Array (UEA) shown in the figure, provide a challenge for current encapsulation techniques. Parylene has been the gold standard for encapsulation of neural and biomedical implants in general due to its well-suited combination of biocompatibility, electrical properties and chemical inertness. However recording capabilities of long-term neural implants (>6 months) encapsulated with Parylene show signs of degradation. To combat this problem Blackrock Microsystems proposes a novel bi-layer encapsulation scheme that combines Plasma Assisted Atomic Layer Deposited (PA-ALD) alumina layer underneath the Parylene layer. This encapsulation scheme, novel to biomedical field, will retain all the advantages of Parylene while utilizing vastly superior dielecric properties of underlying ALD alumina layer to create a much longer lasting and more electrically stable biomedical implants. This bi-layer encapsulation scheme may be seamlessly incorporated into our existing fabrication process flow for our flagship product, the UEA. The bi-layer The UEA with integrated electronics encapsulation method will work on different surfaces (metal, semiconductor, polymer, ceramic) and on devices with integrated wireless components making it ideal for coating any complex medical device intended for long term implant. The project has 4 specific aims: Specific Aim 1: Optimize an ALD alumina/Parylene bi-layer encapsulation scheme and compare performance with Parylene-only encapsulation on test devices. Specific Aim 2: Develop etch methods to selectively expose active electrode sites on UEAs coated with optimized ALD alumina/Parylene bi-layer. Specific Aim 3: Evaluate charge injection/impedance characteristics of ALD alumina/Parylene bi-layer coated UEAs. Specific Aim 4: Comparison of in vivo performance of ALD alumina/Parylene bi-layer coated UEAs to Parylene-only coated UEAs. Our preliminary results with Parylene and alumina coated planar interdigitated electrode (IDE) test structures are very promising in support of the proposed work. We have shown that the bi-layer encapsulation yields more stable leakage current, and stable impedance (with <5% change) at 67 �C for about 5 months (approximately equivalent to 40 months at 37 �C). This superior performance of bi-layer encapsulation suggests its potential usefulness for chronic implants with complex surface geometries. At the end of the Phase I 'Lab to Marketplace' SBIR project, Blackrock expects to have developed protocols and standards to transform this research from its current early-stage lab setting into a commercial-grade manufacture process.

描述（由适用提供）：现在正在研究或使用完全植入的电子系统研究或治疗一系列神经系统疾病，以记录或调节人类的大脑活动。这些隐含物目前正在使用包围植入物的聚合物涂层保护并有助于使体液远离敏感电子产品。带有复杂三维几何形状的大脑含义，例如图中所示的犹他州电极阵列（UEA），为当前的封装技术提供了挑战。由于其非常适合生物相容性，电性能和化学惰性的结合，Parylene一直是整个神经和生物医学齿轮的金标准。然而，用parylene封装的长期神经腔（> 6个月）的记录能力显示出降解的迹象。为了解决这个问题，贝莱德微型系统提出了一种新型的双层封装方案，该方案结合了沉积的血浆辅助原子层（Pa-ald）氧化铝层在parylene层下方。这种封装方案是新颖的生物医学领域，将保留parylene的所有优势，同时利用基础ALD氧化铝层的极优质的二环性特性，从而创造出更长的持久和更稳定的生物医学的imp。该双层封装方案可以无缝地纳入我们旗舰产品UEA的现有制造过程流中。带有集成电子封装方法的双层UEA将在不同的表面（金属，半导体，聚合物，陶瓷）上使用，并在具有集成的无线组件的设备上，使其非常适合涂覆任何用于长期植入物的复杂医疗设备。该项目具有4个特定目的：特定目标1：优化ALD氧化铝/parylene双层封装方案，并将性能与仅帕里伦（Parylene）封装在测试设备上。特定目标2：开发ET方法，以选择性地揭示与优化的ALD氧化铝/parylene双层涂层的UEA上的活性电极位点。特定目标3：评估ALD氧化铝/parylene双层涂层的电荷注入/阻抗特性。特定目标4：比较Ald氧化铝/parylene双层涂层的体内性能与仅戊烯涂层的UEAS的比较。我们的初步结果是在支持拟议的工作的支持下，非常承诺，非常承诺，帕里烯和铝涂层平面互插的电子（IDE）测试结构。我们已经表明，双层封装产生更稳定的泄漏电流，稳定的阻抗（<5％的变化）在67 c持续约5个月（大约相当于37°C时40个月）。双层封装的卓越性能表明，其对具有复杂表面几何形状的慢性侵入的潜在有用性。在第一阶段“实验室到Marketplace” SBIR项目的结束时，BlackRock预计将开发协议和标准，将这项研究从当前的早期实验室环境转变为商业级制造过程。