Mechanical structure of depletion type mosfet, Electrical Engineering

Mechanical Structure of Depletion Type MOSFET

The mechanical structure of this type of device is displayed in figure. In an IC, we would locate two n-type regions side by side in a p-type area and then place the gate in between the n-type regions. Though, the important region still contains the two n-type regions and the p-type area in between them.

Without applied bias, we have what amounts to an npn transistor without base connection. The two n-type regions are electrically separate and isolated from each other. Although with a voltage applied in between the two n-type regions, there is no channel present and no current flow.

563_Mechanical Structure of Depletion Type MOSFET.png

Whereas we still apply the usual positive voltage to the drain with respect to the source, this time we will as well apply a positive voltage to the gate region. This comprises the effect of attracting free electrons in the direction to the gate. The larger the positive gate voltage, the wider its electric field and the much more free electrons it will attract.

You may not think this would have any influence on the p-type region, in which the majority current carriers are holes. Though, there are some free electrons here also. Additionally, the source junction is forward biased, thus the positive gate voltage can attract electrons across this junction towards the gate.

The net result is that the electrons attracted in the direction to the gate actually improve a channel within the p-type region, as displayed in figure. This is a channel that is made up of free electrons, and actually bridges the gap in between source and drain. Now we have a channel that can conduct current from source to drain by the device.

Posted Date: 1/11/2013 1:41:29 AM | Location : United States







Related Discussions:- Mechanical structure of depletion type mosfet, Assignment Help, Ask Question on Mechanical structure of depletion type mosfet, Get Answer, Expert's Help, Mechanical structure of depletion type mosfet Discussions

Write discussion on Mechanical structure of depletion type mosfet
Your posts are moderated
Related Questions
A linear circuit component is one that has a linear I V characteristic

TRAP has the maximum priority There are 2 types of interrupts external and internal. NMI has highest priority between all external interrupts,TRAP has highest priority between

Inductive Logic Programming : Now here having studied a non-symbolic approach to machine learning on Artificial Neural Networks then we return to a logical approach, namely In

What are the different modes in which 8255 Programmable Peripheral Interface (PPI) can operate? Twenty Four I/O lines in 38-bit port groups - A, B and C A and B can be

Consider the circuit of Figure and obtain the complete solution for the voltage v C (t) across the 5-F capacitor and the voltage vx(t) across the 5- resistor.

Q. Mode of propagation of electromagnetic waves? The mode of propagation of electromagnetic waves in free space and atmosphere may be subdivided into three categories: • Gro

Advanatages of GPS system These systems have been developed to mimic the knowledge and expertise of an expert in a particular field. For instance: -  prospecting for minera

Q. A 25-kVA, 2400/240-V, 60-Hz, single-phase transformer has an equivalent series impedance of 3.45 + j5.75  referred to the primary high voltage side. The core loss is 120 W. Whe

Calculation of Aggregate Technical and Commercial Loss The concept of AT&C loss was introduced within 2001-02. The AT&C losses are presently in the range of 18% to 62% in seve

Find a minimum two level, multiple-output AND-OR gate circuit to realize these functions (eight gates minimum). F 1 (a,b,c,d) =Σm(10,11,12,15) +D (4,8,14) F 2 (a,b,c,d) =Σm(4