POLYMERIC PROTECTION OF IMPLANTABLE MICRO-ELECTRONICS

我们的长期目标是开发适合 用于长期可植入微电子器件的封装 集成电路. 集成电路（微型传感器）是 需要提供传感和控制功能，以进一步 植入式电子系统的发展。 目前 存在可用于植入的装置， 神经假体，包括听觉、膀胱、膈肌和 心脏（起搏器）修复装置，上部和下部 四肢功能性神经肌肉刺激系统，颅骨 压力监测器、血液离子和气体传感器以及植入式药物 与低血压控制药物一起使用的输送系统， 胰岛素 在过去的十年中，植入式 集成了超小型集成电路的电子系统 电路传感器和传感器已受到严重限制， 缺乏适用于保护的包装技术 电子设备从生理环境中分离出来。 的 有限尺寸的重要性使得起搏器包装 技术不适用。 本提案包括基本的 这些研究将确定能够 保护长期植入的I.C.传感器的周期 几年，甚至几十年，其目的是： 1. 确定腐蚀控制能力 聚二甲基硅氧烷和聚酰亚胺用于保护 植入的微电子组件。 材料参数，例如 如附着力、硬度、渗透性、伸长率和抗耳裂性 将与性能相关。 2. 评估表面处理技术的有效性 包括涂底漆、清洗、蚀刻和真空烘烤 通过减少金属化腐蚀， 漏电电流 3. 确定影响选择和开发的限制因素 聚合物防水剂， 体外和体内植入式器械。 评价 封装系统将适当考虑 输出导线和生物相容性的特殊问题。 4. 在目前正在进行的传感器上测试改性材料 在我们的实验室里。 这将通过 设计和制造一个超小型接口，从I.C. 到微型柔性电缆。

Our long-term objective is the development of technology suitable for the packaging of chronically implantable micro-electronic integrated circuits. Integrated circuits, (micro-transducers) are needed to provide sensing and control functions to further the development of implantable electronic systems. Presently devices exists which could be used for implantable neuroprostheses, including auditory, bladder, diaphramatic, and cardiac (pacemaker) prosthetic devices, upper and lower extremity functional-neuromuscular-stimulation systems, cranial pressure monitors, blood ion and gas sensors, and implantable drug delivery systems for use with hypotension controlling drugs and insulin. During the past decade, the design of implantable electronic systems which incorporate subminiature integrated- circuit sensors and transducers has been seriously limited by the absence of packaging technologies suitable for the protection of the electronic devices from the physiological environment. The significance of limited sizes makes pacemaker packaging technology inapplicable. The present proposal incorporates basic studies which will identify materials and technologies capable of protecting chronically implanted I.C. transducers for periods of years, even decades, and is aimed at: 1. Determining the corrosion-control capabilities of polydimethylsiloxanes and polyimides used for the protection of implanted micro-electronic assemblies. Material parameters such as adhesion, hardness, permeability, elongation, and ear resistance will be correlated with performance. 2. Evaluating the effectiveness of surface preparation techniques including priming, cleaning, etching, and vacuum bake-out in reducing metallization corrosion through the reduction of electrical leakage currents. 3. Defining constraints affecting the selection and development of polymeric encapsulants for moisture protection of complete implantable devices in-vitro and in-vivo. Evaluation of encapsulation systems will be made with due regard for the special problems of output leads and biocompatibility. 4. Testing the modified materials on a sensor currently under development in our laboratory. This will be accomplished by designing and fabricating a subminiature interface from the I.C. to a miniature flexible electrical cable.