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A test microchip for evaluation of hermetic packaging technology for biomedical prosthetic implants

Kazemi, Mohammad and Basham, Eric and Sivaprakasam, Mohanasankar and Wang, Guoxing and Rodger, Damien and Weiland, James and Tai, Y. C. and Liu, Wentai and Humayun, Mark (2004) A test microchip for evaluation of hermetic packaging technology for biomedical prosthetic implants. In: International Conference of the IEEE Engineering in Medicine and Biology Society, 26th (IEMBS '04), San Francisco, CA, 1-5 September 2004. Vol.2. IEEE , Piscataway, Nj, pp. 4093-4095. ISBN 0-7803-8439-3.

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The development of a test chip that will be used to evaluate a hermetic and biocompatible package for the driving CMOS circuitry of a retinal prosthesis is described. The package design is estimated to be about 2 x 2 x 0.3 mm^3 and will be formed by conformal layers of parylene and a metal (e.g. titanium) as inner and outer protections, respectively. The test chip has been specifically designed for evaluation of the packaging technology. It consists of many blocks of analog and digital components as well as relative humidity and temperature sensors. The test chip has more probe points than a typical chip, allowing a more thorough evaluation of circuit behavior during the testing. This chip will first be coated in a layer of parylene C and soaked in heated isotonic saline for an extended period of time. Every block in the chip will then be tested for functionality using the surface probe points. The next step is to coat the surface of another test chip with parylene and a metal and repeat these soak tests. The results will then be analyzed and mean time-to-failure for the different samples will then be computed. Using the accelerated testing paradigm, these results will then be extrapolated to mean time-to-failure in the operating intraocular environment. Parylene test structures have already undergone an accelerated lifetime test and results have been analyzed.

Item Type:Book Section
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URLURL TypeDescription
Rodger, Damien0000-0002-1583-5946
Tai, Y. C.0000-0001-8529-106X
Humayun, Mark0000-0002-5830-5208
Additional Information:© 2004 IEEE. Reprinted with permission. Publication Date: 1-5 Sept. 2004. This research was performed at the Biomimetic Microelectronics Systems Engineering Research Center. This material is based on work supported by the National Science Foundation under Grant No. EEC-0310723. This work was also supported in part by a grant from the Whitaker Foundation.
Funding AgencyGrant Number
Whitaker FoundationUNSPECIFIED
Subject Keywords:CMOS analogue integrated circuits; CMOS digital integrated circuits; chip scale packaging; eye; humidity sensors; polymer films; prosthetics; temperature sensors; titanium; CMOS circuitry; analog components; biocompatible package; biomedical prosthetic implants; digital components; heated isotonic saline; hermetic packaging technology; intraocular environment; microchip; parylene C; relative humidity; retinal prosthesis; temperature sensors
Record Number:CaltechAUTHORS:KAZembc04
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:12618
Deposited By: Kristin Buxton
Deposited On:15 Dec 2008 23:33
Last Modified:08 Nov 2021 22:31

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