Contents
What is N well resistor?
These resistors are N+ and P+ (used for source/drain of NMOS and PMOS, respectively), N-well (used for the substrate to make PMOS) and heavily doped poly silicon (used for gate metal of MOS). There are two ways one can realize an N-well resistor in the standard CMOS process: N-well device (Fig.
What does S resistor do?
A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active elements, and terminate transmission lines, among other uses.
What is n well?
N-Well Process Step10: Deposition of polysilicon Chemical Vapor Deposition (CVD) process is used to deposit a very thin layer of gate oxide. Step11: Removing the layer barring a small area for the Gates Except the two small regions required for forming the Gates of NMOS and PMOS, the remaining layer is stripped off.
Why is n well used?
The N-well / P-well technology, where n-type diffusion is done over a p-type substrate or p-type diffusion is done over n-type substrate respectively. The silicon On Insulator process, where rather than using silicon as the substrate an insulator material is used to improve speed and latch-up susceptibility.
What is N well process?
Can a simple model be used to model a n-well resistor?
A simple model as well as an advanced model have been used to model both types of resistors. The modeling has been carried out using MATLAB 6.5 and equations derived from device physics. Detailed modeling of an N-well field resistor, which is not generally available in the literature, has been carried out in great details.
Which is not a function of the voltage across the Resis?
There are two ways Most of the important parameters, such as the absolute one can realize an N-well resistor in the standard CMOS value of sheet resistivity, temperature coefficient, unifor- process: N-well device (Fig. 1) and N-well field (Fig. 2) mity, etc., are not a function of the voltage across the resis- [5].
Where are the depletion regions of the N-well device?
Depletion regions exist at the bottom and sidewalls (direction perpendicular to the page) of the N-well region. The width of this depletion region in- creases as the voltage across the resistor increases. The depletion region encroachment and thus the resistance of W V V2 the device will depend on the operating voltage.
What kind of resistors are used for NMOS?
These resistors are N+ and P+ (used for source/drain of NMOS and PMOS, respectively), N-well (used for the substrate to make PMOS) and heavily doped poly silicon (used for gate metal of MOS). Some foundries also use high-resistance poly for high-value resis- tors, which requires additional mask and processing steps.