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<p>This thesis deals with the main aspects in chemical vapordeposition (CVD) of silicon (Si) and silicon-germanium (Si_1-xGe_x) films for high-speed bipolar transistors.<i>In situ</i>doping of polycrystalline silicon (poly-Si)using phosphine (PH₃) and disilane (Si₂H₆) in a low-pressure CVD reactor was investigated toestablish a poly-Si emitter fabrication process. The growthkinetics and P incorporation was studied for amorphous Si filmgrowth. Hydrogen (H) incorporated in the as-deposited films wasrelated to growth kinetics and the energy for H₂desorption was extracted. Film properties such asresistivity, mobility, carrier concentration and grain growthwere studied after crystallization using either furnaceannealing or rapid thermal annealing (RTA). In order tointegrate an epitaxial base, non-selective epitaxial growth(NSEG) of Si and SiGe in a lamp-heated single-waferreduced-pressure CVD reactor was examined. The growth kineticsfor Si epitaxy and poly-Si deposition showed a differentdependence on the deposition conditions i.e. temperature andpressure. The growth rate difference was mainly due to growthkinetics rather than wafer surface emissivity effects. However,it was observed that the growth rate for Si epitaxy and poly-Sideposition was varying during growth and the time-dependencewas attributed to wafer surface emissivity variations. A modelto describe the emissivity effects was established, taking intoconsideration kinetics and the reactor heating mechanisms suchas heat absorption, emission andconduction. Growth ratevariations in opening of different sizes (local loading) andfor different oxide surface coverage (global loading) wereinvestigated. No local loading effects were observed, whileglobal loading effects were attributed to chemical as well astemperature effects. Finally, misfit dislocations formed in theSiGe epitaxy during NSEG were found to originate from theinterface between the epitaxial and polycrystalline regions.The dislocations tended to propagate across the activearea.</p><p><b>Keywords:</b>chemical vapor deposition (CVD), bipolarjunction transistor (BJT), heterojunction bipolar transistor(HBT), silicon-germanium (SiGe), epitaxy, poly-Si emitter,<i>in situ</i>doping, non-selective epitaxy (NSEG), loadingeffect, emissivity effect</p>

<p>Heterojunction bipolar transistors (HBT) based on SiGeC havebeen investigated. Two high-frequency architectures have beendesigned, fabricated and characterized. Different collectordesigns were applied either by using selective epitaxial growthdoped with phosphorous or by non-selective epitaxial growthdoped with arsenic. Both designs have a non-selectivelydeposited SiGeC base doped with boron and a poly-crystallineemitter doped with phosphorous.</p><p>Selective epitaxial growth of the collector layer has beendeveloped by using a reduced pressure chemical vapor deposition(RPCVD) technique. The incorporation of phosphorous and defectformation during selective deposition of these layers has beenstudied. A major problem of phosphorous-doping during selectiveepitaxy is segregation. Different methods, e.g. chemical orthermal oxidation, are shown to efficiently remove thesegregated dopants. Chemical-mechanical polishing (CMP) hasalso been used as an alternative to solve this problem. The CMPstep was successfully integrated in the HBT process flow.</p><p>Epitaxial growth of Si1-x-yGexCy layers for base layerapplications in bipolar transistors has been investigated indetail. The optimization of the growth parameters has beenperformed in order to incorporate carbon substitutionally inthe SiGe matrix without increasing the defect density in theepitaxial layers.</p><p>The thermal stability of npn SiGe-based heterojunctionstructures has been investigated. The influence of thediffusion of dopants in SiGe or in adjacent layers on thethermal stability of the structure has also been discussed.</p><p>SiGeC-based transistors with both non-selectively depositedcollector and selectively grown collector have been fabricatedand electrically characterized. The fabricated transistorsexhibit electrostatic current gain values in the range of 1000-2000. The cut-off frequency and maximum oscillation frequencyvary from 40-80 GHz and 15-30 GHz, respectively, depending onthe lateral design. The leakage current was investigated usinga selectively deposited collector design and possible causesfor leakage has been discussed. Solutions for decreasing thejunction leakage are proposed.</p><p><b>Key words:</b>Silicon-Germanium-Carbon (SiGeC),Heterojunction bipolar transistor (HBT), chemical vapordeposition (CVD), selective epitaxy, non-selective epitaxy,collector design, high-frequency measurement, dopantsegregation, thermal stability.</p>

I studien undersöks hur bildlärare kan arbeta med frågor som rör sexualitet, relationer, samt sex- och samlevnad i bildundervisning. Undersökningen rör även hur elever kan stödjas i sin identitet genom normkritisk bildundervisning som tar upp frågor kring sexualitet och relationer. Metoden är kvalitativa och tar avstamp ur djupintervjuer med personer som arbetar med bildundervisning och ämnesintegrerad sex- och samlevnadsundervisning. Resultatet visar att sex- och samlevnadsundervisning är mest effektiv när den är ämnesintegrerad. I bildämnet finns det många olika ingångar och verktyg inom arbetsområdet som bl.a. skapar tillfällen att diskuterar relationer och värderingar, medvetgörandet av normer och stereotyper, samt uttryck och undersökande av den identiteter. Genom att använda sig av olika kreativa läroprocesser och horisontell mediering så kan elever förstå sin egen person och kropp, samt sig själv i relation till andra och till samhället. Detta är en god förutsättning för identitetsskapande och för ett kreativt och välfungerande liv.

Recently, several SiGe HBT devices fabricated on CMOS-compatible silicon on insulator (SOI) substrates (SiGe HBTs-on-SOI) have been demonstrated, combining the well-known SiGe HBT performance with the advantages of SOI substrates. These new devices are especially interesting in the context of extreme environments - highly challenging surroundings that lie outside commercial and even military electronics specifications. However, fabricating HBTs on SOI substrates instead of traditional silicon bulk substrates requires extensive modifications to the structure of the transistors and results in significant trade-offs. The present work investigates, with measurements and TCAD simulations, the performance and reliability of SiGe heterojunction bipolar transistors fabricated on silicon on insulator substrates with respect to operation in extreme environments such as at extremely low or extremely high temperatures or in the presence of radiation (both in terms of total ionizing dose and single effect upset).

Den här uppsatsen har haft som syfte att undersöka hur fem unga transsexuella upplevt sin skoltid och hur detta har påverkat deras identitetsskapande. De tre frågeställningarna har varit: Hur har intervjupersonerna skapat sin könsöverskridande identitet i en skolkontext? Vilka är de praktiker och diskurser som de format och formar sina "jag" genom? Mot vilka diskurser, om några, gör de intervjuade personerna motstånd genom sitt identitetsskapande? Uppsatsen poängterar att forskning inom utbildningsvetenskap med koppling till sexualitets- och identitetspolitik är essentiellt för lärarutbildningens och läraryrkets utveckling. Det finns redan uttryckligen formulerat i styrdokumenten men verkligheten i verksamheten tycks se annorlunda ut. Skolan har ansvar för alla barn och unga som befinner sig i verksamheten. Man kan därför inte blunda för de rapporter om ohälsa och utsatthet som redovisats av statliga institutioner såsom Folkhälsoinstitutet och Ungdomsstyrelsen. / This thesis originates from an experienced lack of knowledge within the teacher trainee program. The lack consists of a close to non-existent information of the LGBT-group as a norm breaking group of students in our schools. This essay focuses in particular on the transgender group. The essay claims that this lack of knowledge within our schools leads to discrimination against students which can cause health problems. But most importantly it complicates the identity formation process of young transgender people.

HBT-personer rapporterar lika stor, eller större utsatthet för våld i nära relationer jämfört med heterosexuella personer. Tröskeln att söka hjälp vid våldsutsatthet är hög. Ett sätt att förbättra omhändertagandet är att bidra med mer kunskap inom området. En metaanalys är en vetenskaplig metod som sammanfattar resultat från flera studier men har knappt använts inom området våld i nära relationer bland HBT-personer. Våra resultat visar att homosexuella män har 80 procent ökad risk att utsättas för våld jämfört med heterosexuella män, och homosexuella kvinnor har 15 procent ökad risk jämfört med heterosexuella kvinnor. Bisexuella män var inte mer utsatta för våld i jämförelse med homosexuella män, men bisexuella kvinnor hade 36 procent ökad risk jämfört med homosexuella kvinnor. Transpersoner hade 75 procent ökad risk jämfört med cispersoner, men sambandet kunde inte säkerställas. Dessa resultat kan öka förståelsen, förbättra omhändertagandet och minska barriären för utsatta HBT-personer att söka hjälp. / LGBT individuals report similar or greater risk of intimate partner violence (IPV) in comparison with heterosexuals. However, the barrier to seek help is high when exposed to IPV, and one way to improve the care of LGBT individuals is presenting firm knowledge. Meta-analysis is a scientific method which summarizes results from many studies but has rarely been used in this area. Our results showed that homosexual men had 80 percent greater risk of being exposed to IPV in comparison with heterosexual men. Homosexual women had 15 percent greater risk in comparison with heterosexual women. Bisexual men were not more exposed than homosexual men, however bisexual women had 36 percent greater risk of being exposed than homosexual women. Transgender individuals had 75 percent greater risk of being exposed in comparison with cisgender, although not significant. These results enhance our understanding of IPV and could improve support of those exposed to IPV.

Although the majority of wireless receiver subsystems have moved to digital signal processing over the last decade, the low noise amplifier (LNA) remains a crucial analogue subsystem in any design being the dominant subsystem in determining the noise figure (NF) and dynamic range of the receiver as a whole. In this research a novel LNA configuration, namely the LC-ladder and capacitive shunt-shunt feedback topology, was proposed for use in the implementation of very wideband LNAs. This was done after a thorough theoretical investigation of LNA configurations available in the body of knowledge from which it became apparent that for the most part narrowband LNA configurations are applied to wideband applications with suboptimal results, and also that the wideband configurations that exist have certain shortcomings. A mathematical model was derived to describe the new configuration and consists of equations for the input impedance, input return loss, gain and NF, as well as an approximation of the worst case IIP3. Compact design equations were also derived from this model and a design strategy was given which allows for electronic design automation of a LNA using this configuration. A process for simultaneously optimizing the circuit for minimum NF and maximum gain was deduced from this model and different means of improving the linearity of the LNA were given. This proposed design process was used successfully throughout this research. The accuracy of the mathematical model has been verified using simulations. Two versions of the LNA were also fabricated and the measured results compared well with these simulations. The good correlation found between the calculated, simulated and measured results prove the accuracy of the model, and some comments on how the accuracy of the model could be improved even further are provided as well. The simulated results of a LNA designed for the 1 GHz to 18 GHz band in the IBM 8HP process show a gain of 21.4 dB and a minimum NF of only 1.7 dB, increasing to 3.3 dB at the upper corner frequency while maintaining an input return loss below -10 dB. After steps were taken to improve the linearity, the IIP3 of the LNA is -14.5 dBm with only a small degradation in NF now 2.15 dB at the minimum. The power consumption of the respective LNAs are 12.75 mW and 23.25 mW and each LNA occupies a chip area of only 0.43 mm2. Measured results of the LNA fabricated in the IBM 7WL process had a gain of 10 dB compared to an expected simulated gain of 20 dB, however significant path loss was introduced by the IC package and PCB parasitics. The S11 tracked the simulated response very well and remained below -10 dB over the feasible frequency range. Reliable noise figure measurements could not be obtained. The measured P1dB compression point is -22 dBm. A 60 GHz LNA was also designed using this topology in a SiGe process with ƒT of 200 GHz. A simulated NF of 5.2 dB was achieved for a gain of 14.2 dB and an input return loss below -15 dB using three amplifier stages. The IIP3 of the LNA is -8.4 dBm and the power consumption 25.5 mW. Although these are acceptable results in the mm-wave range it was however found that the wideband nature of this configuration is redundant in the unlicensed 60 GHz band and results are often inconsistent with the design theory due to second order effects. The wideband results however prove that the LC-ladder and capacitive shunt-shunt feedback topology is a viable means for especially implementing LNAs that require a very wide operating frequency range and also very low NF over that range. / Thesis (PhD(Eng))--University of Pretoria, 2011. / Electrical, Electronic and Computer Engineering / unrestricted

I studien har jag tittat närmare på medlemmarnas i gaylaget Malmö Devilants tidigareidrottserfarenheter och idrottsbakgrund samt undersökt hur de konstruerar sitt lag vad gällernorm och manlighet. För att uppnå detta gjordes intervjuer med sex av medlemmarna somfick svara på frågor utifrån tre teman: idrottsbakgrund, vardagen i föreningen samt idrottensroll i deras liv. Genom att använda de teoretiska begreppen genus och heteronormativitet harjag därefter analyserat och synat svaren. Utifrån intervjuerna kunde utläsas att alla har olikaupplevelser av idrotten och att alla har någon form av tidigare idrottsbakgrund. Medlemmarnaser också sitt lag som en plats där det heteronormativa inte är den rådande normen, där de kanträffa likasinnade individer med likartade erfarenheter och på så sätt vara en i mängden.Genom att utöva en aktivitet som idrott bryter medlemmarna mot den stereotypa bilden av huren homosexuell man är och de upprätthåller då inte den uppdelning och gräns som ärbetydande för heteronormativiteten. Genussystemet och heteronormen med dess ideal för hurman ska vara för att betraktas som en ”riktig” man/kvinna innebär en begränsning somegentligen inte behöver finnas. Bryts dessa normer upp försvinner förmodligen också debegränsande idealen. / In this study I’ve been taking a closer look at the members of the gay team, Malmo Devilantsand their former sports experience, background in sports, and examined how they constructtheir team. To achieve this, interviews were made with six of the members who were asked toanswer questions based on three themes: background in sports, daily life in the team, and therole of sport in their lives. By using the theoretical concepts of gender and heteronormativity,I have analyzed the answers. Based on the interviews I could see that the members all havedifferent experiences of sport and that everyone has some form of previous sportingbackground. They also see their team as a place where the heteronormativity isn’t theprevailing norm, where members can meet like-minded individuals with similar experiencesand thus become one of the crowd. By exercising an activity such as sports challenge thestereotype of how a gay man is and the members do not maintain the division that issignificance for heteronormativity. The gender system and heteronormativity with its ideals ofhow to be to qualify as a “real” man/woman is a limitation that does not really need to exist.The more the norm and the system dissolves our notions of what is considered male or femalewill probably decrease.

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