Electron transport in ultra-thin strained InGaAs MOS devices

doctoral thesis

• Title (croatian): Transport elektrona u ultratankim napregnutim InGaAs MOS elementima
• Author: Sabina Krivec
• Mentor: Tomislav Suligoj (mentor)
• Committee member: Tomislav Suligoj (član povjerenstva)
• Granter: University of Zagreb; Faculty of Electrical Engineering and Computing; (Department of Electronics, Microelectronics, Computer and Intelligent Systems); Zagreb
• Defense date and country: 2018, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Computing; Data Processing
• Universal decimal classification (UDC): 621.3 - Electrical engineering

Abstract

This doctoral thesis describes research results in the area of physics-based electron transport modelling and simulations of unstrained and strained InGaAs ultra-thin body (UTB) devices. The objective of this thesis was to obtain the impact of strain and body thickness scaling on electron mobility for InGaAs UTB devices. Furthermore, the aim was to investigate the features of electron mobility in InGaAs UTB devices with different gate-oxide materials and surface orientations. In addition, band-structure modelling and calculations were performed in order to assess the impact of strain on the electron mobility. The influence of Fermi level pinning (FLP) was investigated and its relationship with the tensile strain is explained. Finally, the strain and body thickness dependent analytical model suitable for integration in commercially available Technology CAD (TCAD) was developed. The original scientific contribution consists of the following: (i) Physics-based electron mobility model for InGaAs MOS devices including the impact of strain, band-structure effects and Fermi level pinning, (ii) Assessment of electron mobility in ultra-thin strained InGaAs MOS devices including the effect of channel thickness scaling and all relevant scattering mechanisms, (iii) Analytical model of electron mobility in ultra-thin unstrained and strained InGaAs MOS transistors suitable for integration into numerical device simulators.

Abstract (croatian)

Ovaj doktorski rad rezultat je istraživanja u području numeričkog modeliranja i simulacija pokretljivosti elektrona unutar ultratankih (engl. ultra-thin body, UTB) InGaAs elektroničkih elemenata s naprezanjem kristalne rešetke poluvodiča ili bez naprezanja. Cilj ovog istraživanja detaljna je analiza utjecaja naprezanja i smanjenja debljine kanala na pokretljivost elektrona u UTB InGaAs elektroničkim elementima. Također, cilj je odrediti utjecaj različitih vrsta dielektrika ispod upravljačke elektrode te orijentacije aktivne površine na karakteristike UTB InGaAs MOS elemenata. Modeliranje strukture energijskih pojaseva potrebno je kako bi se odredio utjecaj naprezanja i smanjenja debljine tijela na pokretljivost elektrona. Nadalje, ispitan je utjecaj zapinjanja Fermijeve razine (engl. Fermi level pinning, FLP) na pokretljivost elektrona i doveden u odnos s utjecajem naprezanja. Također je razvijen analitički model pokretljivosti prilagođen za ugradnju u numeričke simulatore elektroničkih elemenata. Izvorni znanstveni doprinos ostvaren je u sljedećem: (i) Fizikalni model pokretljivosti elektrona za InGaAs MOS elemente s uključenim efektima naprezanja, strukture energijskih pojaseva i zapinjanja Fermijeve razine, (ii) Određivanje pokretljivosti elektrona u ultratankim napregnutim InGaAs MOS elementima pod utjecajem skaliranja debljine tijela s uključenim svim relevantnim mehanizmima raspršenja, (iii) Analitički model pokretljivosti elektrona u ultratankim InGaAs MOS tranzistorima s ili bez naprezanja prikladan za ugradnju u numeričke simulatore elektroničkih elemenata.

• Keywords: indium-gallium-arsenide (InGaAs); ultra-thin body; semiclassical electron mobility model; momentum relaxation time approximation; high-κ gate dielectrics; surface orientation; nearest neighbour tight binding method; Fermi level pinning; interface states charge; Coulomb scattering; strain
• Keywords (croatian): indij-galij-arsenid (InGaAs); ultra-tanko tijelo; poluklasično modeliranje pokretljivosti elektrona; aproksimacija vremena relaksacije momenta; dielektrici visoke dielektrične konstante; orijentacija aktivne površine; metoda jake veze; zapinjanje Fermijeve razine; gustoća površinskih stanja; Coulombovo raspršenje; naprezanje kristalne rešetke
• Language: english
• URN:NBN: urn:nbn:hr:168:651466
• Study programme: Title: Electrical Engineering and Computing; Study programme type: university; Study level: postgraduate; Academic / professional title: Doktor znanosti elektrotehnike i računarstva (Doktor znanosti elektrotehnike i računarstva)
• Type of resource: Text
• Extent: 117 str. ; 30 cm.
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2019-04-02 15:08:57