MOSFET gates

From the transconductance expressions we see that the first (eq. 15) is linear with Vds and the second (eq. 16) is related to both MOSFET gate voltage Vgs and its threshold voltage Vt- In both cases Cox plays an important role. In fact in order to increase the sensitivity, the gate oxide thickness should be as thin as possible. gm,SAT, according to equation 16, depends on Vt and it is known that Vt depends on Vfb-, the flat band voltage, according to ... 

Figure 4.15. Cross-section HRTEM images of next-generation MOSFET gates. Reproduced with permission from Intel Corporation (http //www.intel.com).

The use of intricate structures and submicron-sized components increases the influence of the composition, structure, and morphology of poly-Si films on the performance of MOSFET gates, loading resistors and capacitors in memory elements, contacts, and interconnects [1-3], A critical issue in this context is to reduce the surface roughness of poly-Si films and enhance the stability of their properties to high-temperature processing. 

By examination of (6.33) it becomes clear that in the absence of device area constraints if 1// noise can be avoided, it is desirable to increase the MOSFET gate width W until C3 = 3. In this case Cj includes the capacitance introduced by the switch Sj. With C3 = 3 the minimum detectable charge will be... 

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