ABACUS—Introduction to Semiconductor Devices
- Version 43
- by Gerhard Klimeck
- Version 61
- by Shawn Rice
Deletions or items before changed
or items after changed
When we hear the
When we hear the semiconductor device, we may think first of the transistors in PCs or video game consoles, but transistors are the basic component in all of the electronic devices we use in our daily lives. Electronic systems are built from such as transistors, capacitors, wireslightemitting diodes and semiconductor lasers. These components are typically integrated into a single chip made of a semiconductor material.
Almost every Electrical Engineering
Almost every Electrical Engineering the fundamental concepts of semiconductor devices. These concepts typically include lattices, crystal structure, bandstructure, band models, carrier distributions, drift, diffusion, pn junctions, solar cells, light-emitting diodes, bipolar junction transistors (BJT), metal-oxide semiconductor capacitors (MOS-), and multi-acronym-device fieldeffect transistors (mad-FETs).
Advanced courses go more deeply into semiconductor theory, device physics, fabrication processes,
Advanced courses go more deeply into semiconductor theory, device physics, fabrication processes, advanced and special purpose devices, such as heterostructure devices, power devices, and optoelectronic devices.
This nanoHUB "topic page" provides an easy access to selected nanoHUB
This nanoHUB "topic page" provides an easy access to selected nanoHUB that is openly accessible.
We invite to participate in this open source, interactive educational initiative:
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|22||== Crystal Structures, Lattices ==|
|25||=== [/tools/abacus Crystal Viewer] ===|
[[Image(/site/resources/tools/crystal_viewer/buckyball.jpg, 120, right)]] [[Image(/site/resources/tools/crystal_viewer/si.jpg, 120, right)]] [[Image(/site/resources/tools/crystal_viewer/fcc.jpg, 120, right)]] [[Image(/site/resources/tools/crystal_viewer/bcc.jpg, 120, right)]]
The [/resources/5065 Crystal Viewer in ABACUS] enables the interactive visualization different Bravais lattices, crystal planes, and materials (diamond, , , , graphene, buckyball).
It is supported by homework assignment in
|34||[/site/resources/2008/01/03815/crystal_hw1.doc MS Word] and [/site/resources/2008/01/03816/crystal_hw1.pdf Adobe PDF] format.|
[/topics/CrystalViewerPage Crystal Viewer Tool Learning Materials] - Comprehensive set of learning materials for the Crystal Viewer Tool.
|42||== Band Models / Band Structure ==|
=== [/tools/abacus Constant Potential Barriers Lab] ===
|75||=== [/tools/abacus Periodic Potential Lab] ===|
[[Image(/site/resources/tools/kronig_penney/stepwell_ek_with_effmass_ek.png, 120, right)]] [[Image(/site/resources/tools/kronig_penney/expanded_ek_free_electron_ek_stepwell.png, 120, right)]] [[Image(/site/resources/tools/kronig_penney/stepwell_functional_with_energy.png, 120, right)]] [[Image(/site/resources/tools/kronig_penney/allowed_bands_step_well.png, 120, right)]]
The [/resources/5065 Periodic Potential Lab in ABACUS] solves the time independent Equation in a -spatial potential variation. Rectangular, triangular, parabolic (harmonic), and Coulomb potential confinements can be considered. The user can determine energetic and spatial details of the potential profiles, compute the allowed and forbidden bands, plot the bands in a compact and an expanded zone, and compare the results against a simple effectivemass parabolic band. Transmission is also calculated through the well for the given energy range.
[/topics/PPLPage Periodic Potential Lab Learning Materials] - Comprehensive set of learning materials for the Periodic Potential Lab.
=== [/tools/abacus Lab] ===
The [/tools/abacus Lab in ABACUS] enables the study of bulk dispersion relationships of , , . The users can apply tensile and compressive strain and observe the variation in the , bandgaps, and effective masses. Advanced users can study effects in ultra-scaled (thin body) quantum wells, and nanowires of different cross sections. Lab uses the ''sp3s*d5'' tightbinding method to compute E(k) for bulk, planar, and nanowire semiconductors.
[/topics/BSLPage Band Structure Lab Learning Materials] - Comprehensive set of learning materials for the Band Structure Lab.
|106||== Bulk Semiconductors ==|
|108||=== [/tools/abacus Carrier Statistics Lab] ===|
[[Image(/site/resources/tools/fermi/cd_carrierdensity.jpg, 120, right)]]
[[Image(/site/resources/tools/fermi/cd_fermi1.jpg, 120, right)]]
The [/tools/abacus Carrier Statistics Lab in ABACUS] demonstrates electron and holedensity distributions based on the Fermi-Dirac and MaxwellBoltzmann equations. This tool shows the dependence of carrier density, density of states and occupation factor on temperature and fermi level. can choose between doped and undoped semi-conductors. , , and can be studied as a function of doping or Fermi level, and temperature. is supported by a [/resources/3878/ homework assignment] in which are asked to explore the differences between Fermi-Dirac and Maxwell-Boltzmann distributions, compute electron and hole concentrations, study temperature dependences, and freeze-out.
[/topics/CarrierStatisticsPage Carrier Statistics Lab Learning Materials] - Comprehensive set of learning materials for the Carrier Statistics Lab.
|126||=== [/tools/abacus Drift Diffusion Lab] ===|
[[Image(/site/resources/tools/semi/excess_carrier_intrinsic_slab_bias.png, 120, right)]] [[Image(/site/resources/tools/semi/excess_carrier_profile_light_left.png, 120, right)]] [[Image(/site/resources/tools/semi/excess_carrier_profile_light_top.png, 120, right)]]
The [/resources/5065 Drift Diffusion Lab in ABACUS] enables to understand the basic concepts of and of carriers inside a semiconductor slab using different kinds of experiments. Experiments like shining light the semiconductor, applying biasboth can be performed. This tool provides important information about carrier densities, transient and steady state currents, -levels and electrostatic potentials. It is supported by two related homework assignments [/resources/4191/ #1] and [/resources/4188/ #2] in which are asked to explore the concepts of drift, diffusion, quasi Fermilevels, and the response to light.
[/topics/DriftDiffusionPage Drift-Diffusion Lab Learning Materials] - Comprehensive set of learning materials for the Drift-Diffusion Lab.
|137||== PN Junctions ==|
|139||=== [/tools/abacus/ PN Junction Lab] ===|
[[Image(/site/resources/tools/pntoy/pntoy3.gif, 120, right)]] [[Image(/site/resources/tools/pntoy/pntoy2.gif, 120, right)]] [[Image(/site/resources/tools/pntoy/pntoy1.gif, 120, right)]] [[Image(/site/resources/tools/pntoy/pnjunction.gif, 120, right)]]
[/tools/abacus/ PN-Junction Lab in ABACUS] need to explore and teach the basic concepts of P-N junction devices. Edit the doping concentrations, change the materials, tweak minoritycarrier lifetimes, and modify the ambient temperature. Then, see the effects in the energy band diagram, carrier densities, net charge distribution, I/Vcharacteristic, .
|145||There is a significant set of associated resources available for this tool.|
|146||* a [/site/resources/tools/pntoy/pnjunction.swf demo of this tool]|
|147||* a [/resources/980/ Primer on Semiconductor Device Simulation].|
* a Learning Module entitled [/resources/68/ PN Junction Theory and Modeling]
* a Learning Module entitled [/resources/68/ PN Junction Theory and Modeling] walks students through the PNjunction theory and let's them verify concepts through on-line simulation.
|149||* Homework assignment on the [/resources/893/ depletion approximation (on the undergraduate level)]|
* Homework assignment on the [/resources/932/ depletion approximation (
* Homework assignment on the [/resources/932/ depletion approximation (the level)]
[/topics/PNDiode PN Junction Lab Learning Materials] - Comprehensive set of learning materials for the PN Junction Lab.
|166||== Bipolar Junction Transistors (BJT) ==|
|168||=== [/tools/abacus/ Bipolar Junction Lab] ===|
[[Image(/site/resources/tools/bjt/3npn_gummel.gif, 120, right)]] [[Image(/site/resources/tools/bjt/1npn_input.jpg, 120, right)]] [[Image(/site/resources/tools/bjt/2npn_output.gif, 120, right)]]
The [/tools/abacus/ Bipolar Junction Lab in ABACUS] allows Bipolar Junction Transistor (BJT) simulation using a 2D mesh. It allows to simulate npnor pnptype of device. Users can specify the , and region depths and doping densities. Also the material and minoritycarrier lifetimes can be specified by the user. is supported by a [/resources/4185/ homework assignment] in which are asked to find the emitter efficiency, the base transport factor, current gains, and the Early voltage. Alsoa qualitative discussion.
[/topics/BJTLabPage BJT Lab Learning Materials] - Comprehensive set of learning materials for the BJT Lab.
|185||== MOS Capacitors ==|
|187||=== [/tools/abacus/ MOScap] ===|
[[Image(/site/resources/tools/moscap/moscap2.gif, 120, right)]] [[Image(/site/resources/tools/moscap/moscap3.gif, 120, right)]] [[Image(/site/resources/tools/moscap/moscap.jpg, 120, right)]]
The [/tools/abacus/ MOScap Tool in ABACUS] enables a semi-classical analysis of MOS. the capacitance of bulkand dualgate capacitors for a variety of different device sizes, geometries, temperatureand doping profiles.
[/topics/MOSCAPPage MOSCap Learning Materials] - Comprehensive set of learning materials for the MOSCap Tool.
|210||== MOSFETs ==|
|212||=== [/tools/abacus/ MOSfet Lab] ===|
[[Image(/site/resources/tools/mosfet/1mosfet.gif, 120, right)]] [[Image(/site/resources/tools/mosfet/mosfet.jpg, 120, right)]]
The [/tools/abacus/ MOSfet Lab in ABACUS] tool enables a semi-classical analysis of current-voltage characteristics for bulk and SOI FieldEffect Transistors (FETs) for a variety of different device sizes, geometries, temperatureand doping profiles.
[/topics/MOSFETLabPage MOSFet Learning Materials] - Comprehensive set of learning materials for the MOSFet Tool.
|229||== About ABACUS Constituent Tools ==|
The Assembly of Basic Applications for Coordinated Understanding of Semiconductors (ABACUS) has been put together from individual
The Assembly of Basic Applications for Coordinated Understanding of Semiconductors (ABACUS) has been put together from individual tools to educators and students a one-stop-shop in semiconductor education. It therefore benefits tremendously from the hard work that the contributors of the individual tool builders have put into their tools.
|233||As a matter of credit, simulation runs that are performed in the ABACUS tool are also credited to the individual tools, which help the ranking of the individual tools. We do also count the number of usages of the individual tools in the ABACUS tool set, to measure the ABACUS impact and possibly also improve the tool.|
In the description above we do not refer to the individual tools since we want to guide the users to the composite ABACUS tool. We cite the individual tools here explicitly so they are being given the appropriate credit and on their respective tool pages are being linked to this ABACUS topic page.
In the description abovewe do not refer to the individual tools since we want to guide the users to the composite ABACUS tool. We cite the individual tools here explicitly so they are being given the appropriate credit and on their respective tool pages are being linked to this ABACUS topic page.
|249||== Additional Reading and Tools ==|
|251||=== Solar Cells ===|
|253||==== [/tools/adept/ ADEPT] ====|
[[Image(/site/resources/tools/adept/adept2.png, 120, right)]]
[/tools/adept/ ADEPT] is not supported within ABACUS it is a research-oriented tool that enables the study of solar cells for various material systems. A [/site/resources/2007/05/02659/adoc.pdf Reference Manual] and a [/site/resources/2007/05/02660/adept_heterostruct_tutorial.pdf ADEPT Heterostructure Tutorial] are available. The interface is not a simple point-and-click interfaceas for example the PN junction lab, but simulation commands are entered a command .
|258||=== MOS Capacitors with Quantum Corrections===|
|259||==== [/tools/schred/ Schred] ====|
[[Image(/images/tool/schred/schred.jpg, 120, right)]]
[/tools/schred/ Schred] is not formally supported in ABACUS. It contains more advanced quantum mechanical concepts and is a nanoHUB contributed tool. It calculates the envelope wavefunctions and the corresponding bound-state energies in a typical MOS) or --) structure and a typical SOI structure by solving self-consistently the one-dimensional (1D) Poisson equation and the 1D equation.
=== Field Effect Transistors ===
[[Image(/site/resources/tools/nanomos/nanomos2.gif, 120, right)]] [[Image(/site/resources/tools/nanomos/nanomos3.gif, 120, right)]]
[[Image(/site/resources/tools/nanofet/nanofet2.gif, 120, right)]]
[[Image(/site/resources/tools/fettoy/1-fettoy.gif, 120, right)]]
[[Image(/site/resources/tools/fettoy/fettoy1.gif, 120, right)]]
The Field-Effect Transistor has been proposed and in many physical systems, materials, and geometries. A multitude of acronyms have developed around these concepts. The "Many-Acronym-Device-FET" madFETwas born. The author of this document was able to trace an attribute to the acronym madFET from [http://www.utdallas.edu/~frensley/ Bill Frensley] to [http://en.wikipedia.org/wiki/Herbert_Kroemer Herbert Kroemer].
|280||nanoHUB.org hosts a variety of tools that enable the simulation of field effect transisors for a variety of different geometries in a variety of different levels of approximations. There is a [/topics/madfets madFETs topics page] that provides an overview of many of the nanoHUB.org madFET tools.|
=== Technology Computer Aided
=== Technology Computer Aided ===
[[Image(/site/resources/tools/padre/padre.jpg, 120, right)]]
Once students have mastered the basics of semiconductors they may be quite interested in venturing into TCAD. There is a [/topics/atcadlab topics page for aTCADlab] and associated single [/tools/atcadlab aTCADlab] tool that assembles various TCAD tools available on the nanoHUB. Process, device, and circuit simulation is represented in [/tools/atcadlab aTCADlab].