STUDY OF 2-D HEMT DEVICE Tec e & T Science & Under the - PowerPoint PPT Presentation

B TECH PROJECT PRESENTATION 2010 logy hnolog echno STUDY OF 2-D HEMT DEVICE Tec e & T Science & Under the guidance of of Scienc Dr. AJIT KUMAR PANDA DEPT. OF ELECTRONICS &COMMUNICATION ENGG. NIST ,PALUR HILLS BERHAMPUR. ute of titute Instit Presented By tional Ins NAVNIDHI UPADHYAY ROLL NO:200620344 National BISHWAJEET ROLL NO:200626368 Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 WHAT IS A HEMT DEVICE? logy hnolog echno • A HEMT is a field effect transistor Tec incorporating a junction between two e & T Science & materials with different band gaps (i.e., of Scienc a Hetrojunction) as the channel instead of a doped region, as is generally the case ute of for MOSFETs. Due to which we are able to titute achieve high electron mobility. Instit tional Ins National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 PROJECT DESCRIPTION logy hnolog • Find the different scattering principles echno Tec which are there in HEMT device. e & T • Mathematical Modelling of different Science & of Scienc scattering phenomenon and 2- DEG. • Write a FORTRAN program to find the ute of titute solution of the above mathematical model Instit using schrondinger wave equation. tional Ins • Verify our program output with SYNOPSIS National tool. Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 HEMT STRUCTURE logy hnolog echno Tec e & T Science & of Scienc ute of titute Instit tional Ins National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 2-DEG FORMATION logy hnolog echno Tec e & T Science & of Scienc ute of titute Instit tional Ins National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 Additional Construction details logy hnolog echno  GaN(hetero structure) on as Si(subsrtrate) Tec were fabricated with field plates of various e & T Science & dimensions for optimum performance . of Scienc  Proper AI mole fraction in the AlGaN layer ute of which optimize device performance. titute Instit tional Ins  Meshing of all grids of different regions to National form the heterojunction structure Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 Meshing of different layerification logy hnolog echno Tec e & T Science & of Scienc ute of titute Instit tional Ins National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 Benefits of such structural design logy hnolog echno  Enhancement in radio frequency (RF) Tec current – voltage swings was achieved with e & T Science & acceptable compromise in gain, through both of Scienc reduction in the trapping effect and increase in break down voltages. ute of  superior performances at simultaneous high titute frequency, power density, and high thermal Instit tional Ins stability. National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 SCOPE OF HEMT logy hnolog • It can be used in microwave and millimeter echno wave communication, imaging, radar, and Tec e & T radio astronomy or any application where Science & high gain and low noise at high frequencies of Scienc are required. It can be used as single transistors or in the form of an IC called ute of titute MMIC ('monolithic microwave integrated Instit circuit‘). HEMT devices are found in many tional Ins National types of equipment ranging from cellphones to electronic warfare systems such as radar. Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 Added advantage of such structural design logy hnolog  The GaN based HEMT is modeled by taking echno Tec various substrates such as GaN itself, Sapphire e & T Science & and SiC etc. of Scienc  when GaN type material is grown over Silicon ute of means wideband gap material grown over narrow titute band gap material as a result, a 2DEG is formed at Instit tional Ins the Si/GaN interface, due to the conduction band National discontinuity. Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 CONCLUSION logy hnolog echno We saw that the characteristics of hemt Tec device and its application in modern e & T Science & technology as it consumes less power and of Scienc also noise immunant . Scattering phenomenon is observed theorotically . Our ute of titute aim is to have a mathematical model for Instit above via schrodinger wave equation and tional Ins matching result with that of synopsis tool. National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 GaN based HEMT logy hnolog  2 DEG in Al x Ga 1-x N/GaN based echno Tec heterostructures, suitable for high electron e & T mobility transistors, are induced by strong Science & of Scienc polarization effects.  AlGaN/GaN interface are sensitive to a large ute of titute number of different physical properties such as Instit tional Ins polarity, alloy composition, strain, thickness, and National doping of the AlGaN barrier. Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 GaN based HEMT(contd…) logy hnolog echno  Formation of two dimensional electron Tec gases in undoped and doped AlGaN/GaN e & T Science & structures rely both on piezoelectric and of Scienc spontaneous polarization induced effects .  To further improve the potential use of the ute of titute traditional device, a new gate recessed Instit tional Ins structure is proposed in this paper by National introducing a thin layer of In x Ga 1-x N layer to the existing Al x Ga 1-x N/GaN device. Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 GaN based HEMT(contd…) logy hnolog echno  The 3.4 eV band gap in GaN allows 7.5 times Tec e & T as much electric field as for GaAs before Science & avalanche breakdown occurs. of Scienc  The piezoelectric and spontaneous polarization effects result in a high density of 2- ute of titute DEG at the Al x Ga 1-x N/GaN hetero-interface. Instit Therefore, Al x Ga 1-x N/GaN can maintain much tional Ins higher current densities. National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 GaN based HEMT(contd…) logy hnolog echno  AlGaN/GaN HEMTs have emerged as Tec e & T Science & attractive candidates for high voltage, high of Scienc power operation at microwave frequencies. ute of  GaN has a larger peak electron velocity, titute larger saturation velocity, higher breakdown Instit tional Ins voltage, and thermal stability. National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 STRUCTURAL DOMAIN VIEW logy hnolog echno Tec e & T Science & of Scienc ute of titute Instit tional Ins National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 Layers of MODFET(AlGaN/GaN/Si) logy hnolog echno Tec e & T Science & of Scienc ute of titute Instit tional Ins Here silicon is added as substrate so we National have a two 2 DEG structure. Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 DESIGN using SYNOPSYS TCAD logy hnolog echno For our simulation we have used the Tec e & T following tools of Synopsys TCAD- Science & of Scienc  Sentaurus structure Editor  Sentaurus Device ute of titute  Tecplot_SV Instit  Inspect tional Ins National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 DESIGN using SYNOPSYS TCAD(Contd..) logy hnolog echno Sentaurus Structure Editor - Tec  Can be used as a 2D or 3D structure editor. e & T  Structures are generated or edited interactively Science & of Scienc using the graphical user interface.  Features an interface to configure and call the ute of Synopsys meshing engines. titute  It generates the necessary input files for the Instit tional Ins meshing engines, which generate the grid and data National files for the device structure. Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 DESIGN using SYNOPSYS TCAD(Contd..) logy hnolog Creating a structure - echno  the structure of the device is designed using Tec e & T the graphical user interface. Science &  include selecting proper material, selecting of Scienc exact coordinate, creating rectangle region, ute of defining contacts, adding vertices, renaming titute region, saving the model etc. Instit tional Ins National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 DESIGN using SYNOPSYS TCAD(Contd..) logy hnolog echno Tec e & T Science & of Scienc ute of titute Instit tional Ins National Navnidhi Upadhyay & Bishwajeet

B TECH PROJECT PRESENTATION 2010 DESIGN using SYNOPSYS TCAD(Contd..) logy hnolog Mesh Operation - echno  users can define doping profiles and refinement Tec e & T parameters in different parts of the structure. Science & of Scienc  The placement of specified by user-defined refinement/evaluatthese profiles and refinements ute of titute are restricted can be ion (Ref/Eval) windows.  Sentaurus Structure Editor allows the full Instit tional Ins flexibility of definitions and placements available National in the Mesh input syntax. Navnidhi Upadhyay & Bishwajeet