The Encapsulation of Microelectronic Devices for Long-Term Surgical Implantation

Modern microelectronics technology makes possible implants which are both small and complex, provided the problems of encapsulation against the depredations of body fluid can be solved. This paper surveys some of the encapsulation procedures available, commenting on their range of application, and describes some of the experience of this Unit in the various technologies. Attention is drawn to the need to relieve residual tensile stresses in encapsulants when attempting to enclose implants in rigid but permeable cases. This paper concludes with some remarks on hermetic packages.