Multi-chip solutions

Most microhotplate-based chemical sensors have been realized as multi-chip solutions with separate transducer and electronics chips. One example includes a gas sensor based on a thin metal film [16]. Another example is a hybrid sensor system comprising a tin-oxide-coated microhotplate, an alcohol sensor, a humidity sensor and a corresponding ASIC chip (Application Specific Integrated Circuit) [17]. More recent developments include an interface-circuit chip for metal oxide gas sensors and the conccept for an on-chip driving circuitry architecture of a gas sensor array [18,19]. 

It is important to realize that in many designs the limit to integration is not a result of the density of the transistors and other chip components, but a result of the density of the metallization system. An often used solution is to incorporate a multi level metallization system (MLMS). In MLMS, up to four layers of aluminum, separated by dielectric layers, are incorporated to handle the needed interconnects. 

Our 2.5-D floorplanning tool is based on a multi-layer Bounded Slice-Line (BSG) data structure. Basically, a BSG data structure is maintained for each layer of chip in a 2.5-D system and the legality of a floorplan solution inside each layer could be automatically guaranteed. The optimization is performed by a highly... 

We work on amelioration in this explorative work, including better electrodes, electronics, sensor context to overcome deficiencies due to impedance converter, electrodes, hand operation context such as pressure and sweat. More sophisticated instrumentation or (CMOS) circuit integration should be considered. The scalable adaptive multi-sensor interface and PC-based soft-computing subsystem can be harmonized towards System-on-Chip for high-performance and low-power solution in the future. 

Another method is based on a microfiuidic multi-injector (MMI) that combines the functionality of glass micropipette-based assays with integrated microfiuidic valves on a single chip. Pulsatile release of solution using integrated valves made from PDMS has produced... 

Fig. 2.4 Schcane of an ion-selective field effect transistm (ISFET)— flow injection analysis (FIA) system. The soil extract sample, calibration, and base solutions are sequentially introduced through a flow injection line system with multiple inlets, and are transported to a multi-ISFET chip with outputs that continuously change due to the passage of the sample through the flow cell...

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