Type mos capacitor pdf

Berkeley ee143 f2010 lecture 22 1 electrical characteristics of mos devices the mos capacitor voltage components accumulation, depletion, inversion modes. V characterization of mos capacitors using the model 4200. The capacitance depends on the voltage mos capacitor is the series combination of the oxide and the voltage dependent semiconductor capacitances. The electrical characteristics of both n and p type gan metaloxide semiconductor mos capacitors utilizing plasmaenhanced cvdsio2 as the gate dielectric were measured. The mos capacitor consists of a metaloxidesemiconductor structure as illustrated by figure 6. A second metal layer forms an ohmic contact to the back of the semiconductor and is called the bulk contact. Lane department of computer science and electrical engineering. On this channel you can get education and knowledge for general issues and topics. Pdf this work reports on an investigation of capacitancevoltage cv measurement of. The heart of this device is the mos capacitor, which we will study today. For a ptype mos capacitor, the oxide capacitance is mea sured in the strong accumulation region.

Typical mos capacitors and transistors in ics today employ. When the ramp rate is high, the inversion layer does not form and does not have time to equilibrate. For instance for a ptype substrate one finds that for a large negative voltage, vg, applied. Shown is the semiconductor substrate with a thin oxide layer and a top metal contact, referred to as the gate. The mos capacitance can be treated as two capacitances in series, the oxide. At zero applied volt age, the bending of the energy bands is ideally determined by the difference in the work functions of the metal and the semiconductor. This work reports on an investigation of capacitancevoltage cv measurement of metaloxidesemiconductor mos capacitors on high resistivity silicon hrs used as substrate for radiofrequency. Regions of operation for mos capacitor with ptype sc. Let us now look at our particular device mos capacitor with an ntype body substrate.

Depending upon the value of gate voltage applied, the mos capacitor works in. Deep depletion the previous discussions pertain to the condition when the gate voltage is ramped slowly, from accumulation condition to depletion and then to inversion condition. To analyze the mos capacitor we will use the same depletion approximation that we introduced in conjunction with pn junctions. Mos capacitor capacitor under bias for an ntype semiconductor. Electrical characteristics of mos devices the mos capacitor. Voltage components accumulation, depletion, inversion modes effect of channel bias and substrate bias effect of gate oxide charges thresholdvoltage adjustment by implantation capacitance vs. Repeat the derivations yourself for ntype substrate. This is where the volt age is negative enough that the. For still higher magnitudes of bias vg mos capacitor. How the metaloxidesemiconductor layers form a capacitor, what charges are present where, and why we care. The capacitance of a mos structure is voltage dependent since the. The induced interface charge in the mos capacitor is closely linked to the shape of the electron energy bands of the semiconductor near the interface.