Estudamos o processo de dopagem de silício com antimônio por recuo promovido por bombardeamento iônico. Em nossas experiências o sistema filme fino de antimônio de 60 nm de espessura depositado sobre silício monocristalino de orientação <100> foi bombardeado com Ar+ ou Ge+ com energias entre 40 e 800 KeV e doses entre 1,0X1014 e 1,0X1017 cm². As amostras foram submetidas e recozimento térmico rápido a temperaturas entre 950 e 1150 ºC por tempos entre 20 e 60 s ou a recozimento prolongado em forno a 600 ºC por 1h. Algumas amostras foram submetidas a recozimento em duas etapas: prolongado a 600ºC por 1h seguido de recozimento rápido a 1200ºC por 5s. A análise das amostras foi feita empregando-se retroespalhamento Rutherford (RBS), espectrometria Auger e medidas em dispositivos Van der Pauw. Os principais resultados são: i) O processo que governa a implantação por recuo e a mistura balística induzida por colisões secundárias. ii) A concentração máxima de dopante situa-se na superfície e toda região dopada localiza-se a profundidade inferior a 0,1 um. iii) A largura do perfil de implantação independo da energia do projétil, e é função da dose incidente. Doses crescentes geram perfis mais profundos. iv) O bombardeamento com Ar+ resulta em recristalização inadequado do silício. O bombardeamento com Ge+ viabiliza perfeita recristalização do silício e boa substitucionalidade do dopante. / We investigated the doping process of silicon with antimony by means of the recoil implantation method. I our experiments a film of antimony deposited over <100> single cristal silicon was bombarded with Ar+ or Ge+ with energies between 40 and 800 KeV and doses ranging from 1,30C1014 to 1,0X1017 cm². Single step annealing of the bombarded samples was performed either in a Rapid Thermal Annealing (RTA) system or in a conventional furnace. IN the former case temperatures ranged from 950 to 1150 ºC and annealing times from 20 to 60s. In the latter case samples were annealed at 600ºC for 1 hour. The samples were analyzed by means of the Rutherford Backscattering spectrometry (RBS) technique Auger spectrometry and electrical measurements in Van der Pauw devices. The main results are: i) Recoil implantation ir governed by ballistic mixing process of collision cascades generated by the incident ions. ii) The maximum antimony concentration occours at the surface and decays rapidly with depth. The profile extends up to a maximum depth of 0,1um, even after annealing. iii) Antimony depth profile are independent of the bombarding particle’s energy, but are dependent on the dose. iv) Ar + bombardment yields imperfect recrystallization at the silicon substrate. Ge+ bombardment yields perfect recrystallization and good substitutionality of antimony atoms after annealing.

Neste trabalho, medimos a perda de energia de íons de He e B ao longo da direção < 100 > do Si, com energias que vão desde 200 ke V a 4,5 Me V, no primeiro caso, e de 500 ke V a 9 MeV, no segundo. Usamos a técnica de retroespalhamento de Rutherford com amostras do tipo SIMOX, as quais consistem de uma camada de Si monocristalino sobre uma camada de 500 nm de Si02 enterrada numa matriz de Si < 100 >. No método experimental empregado, a perda de energia dos íons canalizados é obtida depois de os mesmos serem retroespalhados em um marcador especialmente utilizado para esse fim. Para ambos os tipos de projétil, a curva da razão a entre os poderes de freamento de canalização e em direções aleatórias exibe um máximo largo e decresce lentamente a energias mais altas, em conseqüência do aumento da contribuição da camada L do Si para o poder de freamento eletrônico, como é indicado por cálculos de Aproximação de Born de Onda Plana (PWBA). / In this work, we have measured the electronic stopping power of He and B ions channeling along the < 100 > direction of Si crystals. The ion energies ranged between 200 keV and 4.5 Me V, in the first case, and between 500 ke V and 9 Me V, in the second one. We have used the Rutherford backscattering technique with SIMOX samples consisting of a Si single-crystal layer on top of a buried layer of 500 nm Si02 built into Si < 100 > wafer. In this exp erimental method, the channeling energy loss is obtained aft er the particles being backscattered at some marker specially used for this purpose . For both types of projectile, the curve of the a ratio between the channeling and random stopping powers has a broad maximum and decreases slowly at high energies dueto the increasing of the contribution of the Si L shell to the electronic stopping power, as indicated by Plane Wave Born Approximation (PWBA) calculations.

Chan, Chor Hoi = 離子阱系統的研究 / 陳楚海. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (p. 98-103). / Abstracts in English and Chinese. / Chan, Chor Hoi = Li zi jing xi tong de yan jiu / Chen Chuhai. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.1.1 --- Review of ion traps --- p.1 / Chapter 1.1.2 --- Review of entanglement in ion trap systems --- p.2 / Chapter 1.1.3 --- Review of RWA and MRWA --- p.3 / Chapter 1.2 --- Continuous frequency modes in different configurations --- p.5 / Chapter 1.2.1 --- Configuration 1: simple one sided cavity --- p.6 / Chapter 1.2.2 --- Configuration 2: displaced cavity --- p.8 / Chapter 1.3 --- Coupling strength in the continuous frequency mode model --- p.10 / Chapter 2 --- Motional Rotating Wave Approximation (MRWA) --- p.12 / Chapter 2.1 --- Introduction --- p.12 / Chapter 2.2 --- Trapped ion in a classical light field --- p.13 / Chapter 2.3 --- MRVVA and a rough estimation of the effect of non-resonant terms --- p.14 / Chapter 2.4 --- Numerical comparison between the MRWA solution and the exact solution --- p.17 / Chapter 2.5 --- Numerical results --- p.18 / Chapter 2.6 --- Calculation in the weak coupling and small η limit --- p.28 / Chapter 3 --- Generation of entanglement between photon and phonon --- p.32 / Chapter 3.1 --- Single-ion model --- p.32 / Chapter 3.2 --- Generation of entanglement between photon and phonon through Raman process --- p.35 / Chapter 3.2.1 --- Resolvent method --- p.35 / Chapter 3.2.2 --- Solutions in the limit \/T / ΩT ≤ / 2ΩT《1 --- p.38 / Chapter 3.2.3 --- The long time wave function --- p.40 / Chapter 3.2.4 --- Generation of entanglement in the first red or blue side-band resonance --- p.41 / Chapter 3.2.5 --- Discussion --- p.43 / Chapter 3.3 --- Generation of entanglement by photon scattering --- p.45 / Chapter 3.3.1 --- Resolvent and the scattering matrix --- p.45 / Chapter 3.3.2 --- The long time wave function --- p.48 / Chapter 3.3.3 --- Discussion --- p.50 / Chapter 4 --- Entanglement between vibrational states of separate ions --- p.55 / Chapter 4.1 --- The cascaded system model --- p.55 / Chapter 4.1.1 --- Introduction and basic ideas --- p.55 / Chapter 4.1.2 --- Resolvent and state evolution --- p.57 / Chapter 4.1.3 --- Time-dependent nature of the entanglement --- p.65 / Chapter 4.2 --- Feedback system --- p.69 / Chapter 5 --- Quantum State Transfer --- p.75 / Chapter 5.1 --- Scattering of a photon --- p.75 / Chapter 5.2 --- Cascaded system --- p.76 / Chapter 5.3 --- Feedback system --- p.78 / Chapter 5.4 --- N injected photons --- p.79 / Chapter 5.5 --- General case --- p.80 / Chapter 5.5.1 --- One injected photon --- p.82 / Chapter 5.5.2 --- N injected photons --- p.83 / Chapter 6 --- Generalization to two ion-chains --- p.85 / Chapter 7 --- Sources of errors --- p.88 / Chapter 7.1 --- Attenuation in optical fiber --- p.88 / Chapter 7.2 --- Inclusion of other states --- p.88 / Chapter 7.3 --- Effect of approximation (3.4) --- p.90 / Chapter 7.4 --- Spontaneous emission --- p.92 / Chapter 8 --- Conclusion --- p.97 / Bibliography --- p.98 / Chapter A --- sin[θ+ η](b + bt)] in Fock state basis --- p.104 / Chapter B --- Adiabatic elimination --- p.105 / Chapter C --- Derivation of the phase operator S in the feedback process --- p.112 / Chapter D --- Quantum trajectory method --- p.114

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Thesis (Ph. D.)--California Institute of Technology, 1987. UM #87-19,702. / Advisor names found in the Acknowledgements pages of the thesis. Title from home page. Viewed 01/15/2010. Includes bibliographical references.

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

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