Adding functionality to microchips by wafer post-processing

Abstract

The traditional microchip processes, stores and communicates electrical information. Here we review an emerging class of microchips that have additional functionality through extra integrated components in the chip. In the final manufacturing stage, layers are added on top of the chip, with a specific property such as sensitivity to ionizing radiation. This paper reviews the technology underlying these monolithic microsystems, including the incorporation of new materials, the unconventional application of photoresist layers, and lowtemperature technology for suspended membranes. The manufacturing of exemplary microsystems, such as the active pixel sensor and liquid-crystal-on-silicon, is detailed. A new class of fully integrated radiation imaging systems is now technologically within reach. r

The pixel readout of Micro Patterned Gaseous Detectors

“…By means of wafer post-processing [7] the Micromegas grid can be integrated directly on top of Silicon wafers [8]. With this technology it will be possible to precisely cover CMOS chip wafers with an amplification grid, resulting in a fully integrated readout device for gaseous detector.…”

Development and Studies of Novel Microfabricated Radiation Hard Scintillation Detectors With High Spatial Resolution

“…It is composed of an EPON epoxy resin, an organic solvent and a photoinitiator. This photoresist is commonly used for MEMS [8] and microfluidic devices [9] but also for the fabrication of micro-pattern gas detectors [10] and X-ray imagers [11]- [13].…”

Novel test structures for temperature budget determination during wafer processing

“…Several existing solutions and potential examples are mentioned in a review on this topic [1]. The impact of post-processing, however, on the quality and lifetime of the underlying CMOS chips should be carefully monitored and be guaranteed.…”

“…Temperature is one of the key parameters to be regarded in post-processing. The maximum allowable temperature for post processing is limited to approximately 425° C [1]. For Silicon-On-Insulator (SOI) technology [2] even more care should be taken.…”