Double Mosfet
Posted : admin On 1/3/2022- Double Musket Assassination
- Mosfet Double Sided Cooling
- Double Moses
- Mosfet Double Pulse Test
- Double Gate Mosfet Thesis
EXICON lateral MOSFETs are designed specifically for high fidelity integrated and power amplifiers. Launched in 1993 and improved in 2015, the current range is optimised to offer great advantages to the design of high-end linear amplifiers. Discover what we can do for you and why you should use Exicon Lateral MOSFETs in your audio designs. Bulk MOSFET Design Optimization. To maximize I EFF and minimize V TH variation, heavy doping near the surface of the channel region should be avoided. Use a steep retrograde channel doping profile to suppress I OFF Si ox ox Si Si ox ox Si t t t t 2 1 / Si ox ox Si t 2 Double-Gate FET Scale length: Structure: Ground-Plane FET Source. The dual gate MOSFET is a useful form of MOSFET which can provide some distinct advantages, especially in RF applications. The dual gate MOSFET can be considered in the same light as the tetrode vacuum tube or thermionic valve.
next generation 3D nano device simulator
2D Tutorial
Ultrathin-body Double Gate FET - DG MOSFET (Double Gate Metal Oxide Semiconductor Field Effect Transistor)
Author:Stefan Birner
-> 2DDoubleGateMOSFET_nn3_05grid.in / *nnp*.in -
input file for the nextnano^{3} and nextnano++ software (2D simulation)-> 3DDoubleGateMOSFET_nn3_05grid.in -
input file for the nextnano^{3} software (3D simulation)
>
Download these input files
If you don't have a password yet, you have to first sign up for a free evaluation license in order to download these input files.
DG MOSFET (Double Gate Metal Oxide Semiconductor Field Effect Transistor)
Double Musket Assassination
The main idea of a Double Gate MOSFET is to control the Si channel very efficiently by choosing the Si channel width to be very small and by applying a gate contact to both sides of the channel. This concept helps to suppress short channel effects and leads to higher currents as compared with a MOSFET having only one gate.
- Double Gate MOSFET (Metal Oxide Semiconductor Field Effect Transistor)
(grown on Si substrate, i.e. unstrained)
The Double Gate MOSFET contains the following regionscluster
region
color
1 1 Source and drain are connected with the Si channel blue 2 2 Source (metal) left 3 3 Drain (metal) right 4 4 5 Gate / Backgate (metal) top/bottom 5 6 7 Doped source and drain region (Si) blue 6 8 The insulating material is SiO_{2}. red (default region)
Both the regions 4 (gate) and 5 (backgate) form the cluster no. 4.
The width of the Si channel is 2 nm.
The distance between the two gates is 6 nm, i.e. the isolating SiO_{2} is 2 nm thick on each side. The width of the two gates is 20 nm.
The distance between source and drain is 60 nm. The widths and the lengths of source, drain, left and right doped source regions are 10 nm x 10 nm each. The length of the 2 nm Si channel (without the square doped source and drain regions) is 40 nm.
Top gate (Schottky barrier 3.445 V)
0 V ... 0.2 VSource (0.0 V)
Drain (0.2 V) Bottom gate (Schottky barrier 3.445 V)
0 V ... 0.2 VSchematic top view of the Double Gate MOSFET
The blue squares (Si) are n-doped with a a concentration of 1x10^{20} cm^{-3}.
The 2 nm channel is n-doped with the same concentration from 20 to 30 and from 50 to 60 nm.$doping-function
Source
doping-function-number = 1 !
Si channel (left)
impurity-number = 1
doping-concentration = 1d2 ! 1 x 10^{20} cm^{-3}
only-region = 0d020d06d016d0 ! xmin xmax ymin ymax
doping-function-number = 2 !
Si channel (right)
impurity-number = 1
doping-concentration = 1d2 ! 1 x 10^{20} cm^{-3}
only-region = 20d030d010d012d0 ! xmin xmax ymin ymax
doping-function-number = 3 !
Drain
impurity-number = 1
doping-concentration = 1d2 ! 1 x 10^{20} cm^{-3}
only-region = 50d060d010d012d0 ! xmin xmax ymin ymax
doping-function-number = 4 !
energy relative to 'nearest' conduction band edge in units of
impurity-number = 1
doping-concentration = 1d2 ! 1 x 10^{20} cm^{-3}
only-region = 60d080d06d016d0 ! xmin xmax ymin ymax
$end_doping-function
$impurity-parameters
impurity-number = 1
impurity-type = n-type
number-of-energy-levels = 1
energy-levels-relative = 0.044d0 ![eV]
degeneracy of energy levels,
degeneracy-of-energy-levels = 2 !2
forn-type
$end_impurity-parameters - At the two gates we apply a Schottky barrier of 3.443 eV:
$poisson-boundary-conditions
top and bottom gate
...
poisson-cluster-number = 3 !
region-cluster-number = 4
applied-voltage = 0d0
boundary-condition-type = schottky
schottky-barrier = 3.443d0
contact-control = voltage
...$end_poisson-boundary-conditions
The source and drain contacts are ohmic.
- Source: 0.0 V
- Drain: 0.2 V
A voltage sweep varies the gate (top gate and bottom gate) voltage from 0 to 2.0 V in 10 steps.$voltage-sweep
Gate:
sweep-number = 1
sweep-active = yes
poisson-cluster-number = 3 !poisson-cluster-number = 3
step-size = 0.1d0
number-of-steps = 10
>1
$end_voltage-sweep - Gridding
Grid lines of the Double Gate MOSFET
Note: The grid lines that are shown in the figure are the material grid lines. The grid lines that one specifies in the input file are the physical grid lines. The material grid lines are placed half-way between the physical grid lines. For more information on the definition of the grid confer this page: Grids and Geometry
Mosfet Double Sided Cooling
How to run the input file...
- The lattice temperature is taken to be 300 Kelvin.
The flow scheme is 4 for a classical self-consistent calculation:
- calculate nonlinear Poisson classically
- calculate current classically
No strain will be considered here. - This time we perform a two-dimensional simulation. The overall simulation domain, that is the real space region in which the device is defined, is taken to be a rectangle having the size 22 nm x 80 nm.
- Just a reminder: If you need additional information about the keywords and their specifiers, you can look them up here.
- Output
- The band structure (conduction and valence bands) will be saved into the directoryband_structure/
.
- The densities (electron densities) will be saved intodensities/
.
- Current data (Fermi levels, current density and I-V characteristics) will be saved intocurrent/
.
- The raw data for the potentials and the Fermi levels (can be read in later in subsequent runs) will be saved intoraw_data/
.
Output files that will be produced are:
- The output files can be read in with the AVS/Express software that can be obtained by Advanced Visual Systems.
AVS output files described in the next three paragraphs:- material_grid.fld
- material_grid.coord
- material_grid.dat
- material_grid.fld
This is an AVS field file specifiying the input files and data format needed for processing the 2D/3D visualisation.# AVS field file !
dimension of data
# !
ndim = 2 !
no. of grid points in y direction
dim2 = 18 !
no. of grid points in x direction
dim1 = 66 !
dimension of data
nspace = 2 !
length of data vector (1 means scalar quantity)
veclen = 1 !
data type - integer/float
data = float !
rectilinear coordinate system
field = rectilinear !
name of data files to be proceeded
label = material_grid2D !
These three lines specify where the data is located in each file:
variable 1 file=material_grid2D.dat filetype=ascii skip=0 offset= 0 stride=1
coord 2 file=material_grid2D.coord filetype=ascii skip=0 offset= 0 stride=1
coord 1 file=material_grid2D.coord filetype=ascii skip=0 offset= 18 stride=1
The y coordinates are located at position 0 to 18 in the filematerial_grid.coord
, x coordinates are located in the same file at position 19 to 84.
The variable data is stored in the.dat
file and is related to the coordinates in a systematic order.- AVS input files:
material_grid.coord, material_grid.dat
- material_grid.coord
Coordinates of the grid, i.e. 18+66 real numbers that specify the grid points on each axis.- material_grid.dat
Contains information about the regions.
Each grid point is specified by a region number as defined in the input file (see table at top of this page).- All other folders contain the same structure for AVS field files:
- *.fld
- *.coord
- *.dat - Now we try to plot some nice pictures of our Double Gate MOSFET...
1) Electron density at 0 V Gate voltage:densities/density2Del_ind000.*
Electron density at 0 V Gate voltage (Drain voltage 0.2 V)
The Si region is n-doped with 1 x 10^{20} cm^{-3} from x=10 to 30 nm and from x=50 to 70 nm. The units of the electron density are 1 x 10^{18} cm^{-3}.
2) Electron density at 0.2 V Gate voltage:densities/density2Del_ind010.dat
Electron density at 0.2 V Gate voltage (Drain voltage 0.2 V)
The Si region is n-doped with 1 x 10^{20} cm^{-3} from x=10 to 30 nm and from x=50 to 70 nm. The units of the electron density are 1 x 10^{18} cm^{-3}.
One can clearly see that the electron density has the highest values at the Si-SiO_{2} interfaces.
Quantum mechanical electron density at 0.2 V Gate voltage (Drain voltage 0.2 V)
The Si region is n-doped with 1 x 10^{20} cm^{-3} from x=10 to 30 nm and from x=50 to 70 nm. The units of the electron density are 1 x 10^{18} cm^{-3}.
One can clearly see that the electron density has the highest values in the middle of the channel and not at the Si-SiO_{2} interfaces. This is because the wave functions tend to zero at the Si-SiO_{2} interfaces.
The peak values in the source and drain regions are due to classical densities because the quantum region did not extend over the whole source and drain regions.
Results
- The current-voltage (I-V) characteristic can be found in the following file:
current/IV_characteristics2D.dat
The drain voltage is kept constant at 0.2 V, the gate voltage varies from 0 to 2.0 V.
The figure shows the I-V characteristics for three different mobility models, compared with the results obtained with a commercial software package. The units for the current in a 2D simulation are [A/m] (but can be adjusted to [A/cm]).- mobility-model-simba-0
(no dependence on electric field)-
mobility-model-simba-2
(mobility depends on parallel electric field)
In this case the current is smaller because the mobility decreases when the applied voltage increases.-
mobility-model-lom
(Lombardi mobility model)
More information on the mobility models can be found here:
(SIMBA mobility model)
- $mobility-model-simba- $mobility-model-lom
(Lombardi mobility model)
Note: This is a classical calculation. So no quantum mechanical effects are included. If you are interested in a quantum mechanical calculation please contact [email protected] For a quantum mechanical calculation, the current is smaller. This is mainly due to the difference in the classical and quantum mechanical electron density.Classical and quantum mechanical electron density as seen when cutting through the Si channel.
(Note: In this figure, the Si channel is larger than 2 nm.)
In the classical simulation, the electron density has its maximum at the SiO_{2}-Si interface.
In the quantum mechanical simulation, however, the electron density is basically zero at the SiO_{2}-Si interface.
3D
-> 3DDoubleGateMOSFET_nn3_05grid.in
In order to test the nextnano³ implementation of the three-dimensional drift-diffusion current, we calculated this Double Gate MOSFET in a three-dimensional simulation. We assume that the structure is homogeneous along the z direction and assume the z direction to be 10 nm long (grid spacing 2 nm). The units of the current are in [A] (current/IV_characteristics3D.dat
). The current has to be divided by the length of the device along the z direction, i.e. by 10 nm, in order to obtain it in units of [A/m]. The 3D results are in agreement with the 2D results.
Double Moses
Comparison of the 2D and 3D nextnano³ results for mobility-model-simba-0. |
Mosfet Double Pulse Test
- Please help us to improve our tutorial. Send comments to
support [at] nextnano.com
.
DOUBLE-DIFFUSED MOS (DMOS)
The figure5.22 shows a double-diffused MOS (DMOS) structure. T he channel length, L, is controlled by the junction de pth produced by the n^{+} and p-type diffusions underneath the gate oxide. L is also the lateral distance between the n^{+} p junction and the p-n substrate junction. The channel length can be made to a smaller distance of about 0.5 micro meters. Thus, this process is similar to the situation with resspect to the base width of a double-diffused bipolar transistor. When a fairly large positive voltage is applied to the gate [>V_{TH}], it will cause the inversion of the p-substrate region underneath thhe gate to n- type , and the n-type surface inversion layer that is produced will act as a conducting channel for the flow of electrons from sou rce to drain.
Figure 5.22 Double-Diffused MOS (DMOS) Structure
From the structure it is known that the n-type substrate is very lightly doped. This will help in making enough space for thee expansion of the depletion region between the p-type diffusion region and the n^{+} drain contact region. Due to this, the breakdown voltage w ill become higher between the drain and source.
Double Gate Mosfet Thesis
Power MOSFET
The Power MOSFET is the three terminal (Gate, Drain and Source), four layer (n^{+}pnn^{+)},Unipolar ( only majority carriers in conduction) semiconductor device.