• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 87
  • 31
  • 29
  • 23
  • 16
  • 12
  • 4
  • 4
  • 4
  • 3
  • 3
  • 2
  • 1
  • Tagged with
  • 246
  • 64
  • 56
  • 46
  • 44
  • 34
  • 34
  • 33
  • 31
  • 28
  • 26
  • 25
  • 25
  • 25
  • 25
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Generation of dicing damage in silicon wafers

Ebbutt, Ralph 08 1900 (has links)
No description available.
22

Shape Optimization of Vertical-type Probe Needle Integrated with Floating Mount Technology

Lee, Jiwon January 2013 (has links)
Wafer probing is a testing process to inspect semiconductor wafers before packaging for defects by checking the electrical conductivity via physical contact between the wafers and the probe card. During the contact process, the shape of the probe needle and the mounting configuration onto the probe card have large influences on the stresses and contact force that the probe needles experience. In this paper, static performance of a vertical-type probe needle integrated with floating mount technology is analyzed with a nonlinear finite element analysis. The comparison between fixed mount and floating mount technologies is a part of the analyses. The geometry of a vertical probe needle is optimized to minimize the stress that occurs during the overdrive process, while maintaining adequate force for proper contact with the wafer. Effects of major overall dimensions of probe needle on the maximum stress and contact force is analyzed first, and then curvature of the probe needle body is optimized by employing a constrained minimization function, fmincon, in MATLAB. The maximum stress in the vertical probe pin at 125 ??m overdrive is effectively reduced from 1339 MPa to 972 MPa by applying floating mount technology over the fixed mount, and further reduced to 666 MPa by applying the optimization scheme. The final optimized design induced the contact force of 5.217 gf, which is in the range of the required contact force of 5 to 8 gf. Fatigue life increased from 19,219 cycles to 108,129 by applying floating mount over fixed mount, and further increased to 830,596 for the optimized design.
23

Agent based diagnostic system for the defect analysis during chemical mechanical polishing (CMP)

Kumar, Akhauri Prakash January 2005 (has links) (PDF)
Zugl.: Stuttgart, Univ., Diss., 2005
24

Entwicklung eines Prozessmodelles zur Analyse und Prognose der Schnittspaltentwicklung beim Draht-Trennläppen von Silizium /

Huttenhuis op Bevers, Stephan. January 2006 (has links)
Zugl.: Aachen, Techn. Hochsch., Diss., 2006.
25

Untersuchung und Optimierung der akustischen Eigenschaften kapazitiver mikromechanischer Ultraschallwandler am Beispiel der medizinischen Diagnostik

Lohfink, Annette January 2005 (has links)
Zugl.: Bremen, Univ., Diss., 2005
26

Entwicklung eines hochpräzisen Justagesystems für die UV-Nanoimprint-Lithographie /

Fuchs, Andreas. January 2006 (has links)
Zugl.: Aachen, Techn. Hochsch., Diss., 2006.
27

RGS-Silizium Materialanalyse und Solarzellenprozessierung /

Hahn, Giso. Unknown Date (has links)
Universiẗat, Diss., 1999--Konstanz.
28

Nano-Bonding of Silicon Oxides-based surfaces at Low Temperature: Bonding Interphase Modeling via Molecular Dynamics and Characterization of Bonding Surfaces Topography, Hydro-affinity and Free Energy

January 2011 (has links)
abstract: In this work, a new method, "Nanobonding" [1,2] is conceived and researched to bond Si-based surfaces, via nucleation and growth of a 2 D silicon oxide SiOxHx interphase connecting the surfaces at the nanoscale across macroscopic domains. Nanobonding cross-bridges two smooth surfaces put into mechanical contact in an O2/H2O mixed ambient below T <200 °C via arrays of SiOxHx molecules connecting into a continuous macroscopic bonding interphase. Nano-scale surface planarization via wet chemical processing and new spin technology are compared via Tapping Mode Atomic Force Microscopy (TMAFM) , before and after nano-bonding. Nanobonding uses precursor phases, 2D nano-films of beta-cristobalite (beta-c) SiO2, nucleated on Si(100) via the Herbots-Atluri (H-A) method [1]. beta-c SiO2 on Si(100) is ordered and flat with atomic terraces over 20 nm wide, well above 2 nm found in native oxides. When contacted with SiO2 this ultra-smooth nanophase can nucleate and grow domains with cross-bridging molecular strands of hydroxylated SiOx, instead of point contacts. The high density of molecular bonds across extended terraces forms a strong bond between Si-based substrates, nano- bonding [2] the Si and silica. A new model of beta-cristobalite SiO2 with its <110> axis aligned along Si[100] direction is simulated via ab-initio methods in a nano-bonded stack with beta-c SiO2 in contact with amorphous SiO2 (a-SiO2), modelling cross-bridging molecular bonds between beta-c SiO2 on Si(100) and a-SiO2 as during nanobonding. Computed total energies are compared with those found for Si(100) and a-SiO2 and show that the presence of two lattice cells of !-c SiO2 on Si(100) and a-SiO2 lowers energy when compared to Si(100)/ a-SiO2 Shadow cone calculations on three models of beta-c SiO2 on Si(100) are compared with Ion Beam Analysis of H-A processed Si(100). Total surface energy measurements via 3 liquid contact angle analysis of Si(100) after H-A method processing are also compared. By combining nanobonding experiments, TMAFM results, surface energy data, and ab-initio calculations, an atomistic model is derived and nanobonding is optimized. [1] US Patent 6,613,677 (9/2/03), 7,851,365 (12/14/10), [2] Patent Filed: 4/30/09, 10/1/2011 / Dissertation/Thesis / Ph.D. Physics 2011
29

Produção de curativos hidrogel e wafer à base de polissacarídeos contendo nanopartículas de ouro sintetizadas in situ

Marques, Morgana Souza January 2017 (has links)
Introduction: Among the curatives available for the treatment of cutaneous wounds, studies demonstrate the benefits of using hydrogel and wafers for dry and exudative wounds respectively. These dressings may serve as a matrix for delivering drugs directly into the wound site. Among the assets that can be incorporated, gold nanoparticles (AuNPs) have anti-inflammatory, antimicrobial and antioxidant properties that can support in the healing process. Objective: The objective of this work was to propose a simultaneous process of synthesis of AuNPs in a solution based on kappa carrageenan (κCG) and locust bean gum (LBG) to produce hydrogel and wafer dressings, applicable to the healing of cutaneous wounds. Methods: Synthesis and stabilization of AuNPs occurred simultaneously with the production of the dressing in κCG, LBG, glycerol (GLI) and/or polyvinyl alcohol (PVA) solution. Ultraviolet-visible spectroscopy, dynamic light scattering, rheological property, scanning electron microscopy, mechanical properties, infrared spectroscopy, swelling and antimicrobial activity were performed. Results: The red staining associated with characteristic surface plasmon resonance band confirmed the synthesis of AuNPs in κCG, LBG, GLI and PVA solution. The increase in Au3+ and PVA concentration are related to the larger and smaller AuNPs respectively. AuNPs interact with hydroxyl and sulfate groups and these interactions are associated with their stabilization and aggregation respectively. The increase in Au3+ concentration was responsible for the drop in viscosity and sol-gel transition temperature. The increase in Au3+ and PVA concentration reduced the mechanical properties of the wafers. Hydrogel and wafer swelled 130 and 660%, respectively, and were applicable in the treatment of mild to moderate dry and exudative wounds. Both synthesized devices did not present halos of inhibition against the microorganisms studied. Conclusion: Solution of κCG, LBG, GLI and / or PVA presents reducing and stabilizing power in the synthesis of AuNPs being able to simultaneously form hydrogels and wafers with potential application in the healing of cutaneous wounds. / Submitted by Morgana Souza Marques (morgana.marques@unisul.br) on 2018-02-27T19:08:05Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação Morgana Souza Marques.pdf: 2770032 bytes, checksum: 4aa794a8e5c85a58f47e13114c058998 (MD5) / Approved for entry into archive by Silvane Cauz (silvane.cauz@unisul.br) on 2018-02-27T19:22:01Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação Morgana Souza Marques.pdf: 2770032 bytes, checksum: 4aa794a8e5c85a58f47e13114c058998 (MD5) / Made available in DSpace on 2018-02-27T19:22:01Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação Morgana Souza Marques.pdf: 2770032 bytes, checksum: 4aa794a8e5c85a58f47e13114c058998 (MD5) Previous issue date: 2017 / Introdução: Dentre os curativos disponíveis para o tratamento de feridas cutâneas, estudos comprovam os benefícios da utilização do hidrogel e wafers em feridas secas e exsudativas respectivamente. Esses curativos podem servir como uma matriz para a liberação de fármacos diretamente no local da ferida. Dentre os ativos que podem ser incorporados, as nanopartículas de ouro (AuNPs) possuem propriedades anti-inflamatória, antimicrobiana e antioxidante que podem auxiliar no processo de cicatrização. Objetivo: O objetivo deste trabalho foi propor um processo simultâneo de síntese de AuNPs em solução à base de kappa carragenana (κCG) e alfarroba (LBG) para produção dos curativos hidrogel e wafer, aplicáveis na cicatrização de feridas cutâneas. Métodos: A síntese e estabilização das AuNPs ocorreu simultaneamente com a produção do curativo em solução de κCG, LBG, glicerol (GLI) e/ou polivinil álcool (PVA). Análises como espectroscopia ultravioleta-visível, espalhamento de luz dinâmico, propriedade reológica, microscopia eletrônica de varredura, propriedade mecânica, espectroscopia no infravermelho, intumescimento e atividade antimicrobiana foram realizadas. Resultados: A coloração vermelha associada com banda de ressonância de plasmon de superfície característica confirmaram a síntese de AuNPs em solução de κCG, LBG, GLI e PVA. O aumento da concentração de Au3+ e PVA estão relacionados à síntese AuNPs maiores e menores respectivamente. As AuNPs interagem com grupamentos hidroxilas e sulfatos sendo essas interações associadas à sua estabilização e agregação respectivamente. O aumento da concentração de Au3+ foi responsável pela queda da viscosidade e temperatura de transição sol-gel. O aumento da concentração de Au3+ e de PVA reduziu as propriedades mecânicas dos wafers. Hidrogel e wafer intumesceram respectivamente 130 e 660 % sendo aplicáveis no tratamento de feridas secas e exsudativas com grau leve a moderado. Ambos os dispositivos sintetizados não apresentaram halos de inibição frente aos microrganismos estudados. Conclusão: Solução de κCG, LBG, GLI e/ou PVA apresenta poder redutor e estabilizante na síntese de AuNPs sendo capaz de formar simultaneamente hidrogéis e wafers com potencial aplicação na cicatrização de feridas cutâneas.
30

Scheduling of Wafer Test Processes in Semiconductor Manufacturing

Lu, Yufeng 16 November 2001 (has links)
Scheduling is one of the most important issues in the planning of manufacturing systems. This research focuses on solving the test scheduling problem which arises in semiconductor manufacturing environment. Semiconductor wafer devices undergo a series of test processes conducted on computer-controlled test stations at various temperatures. A test process consists of both setup operations and processing operations on the test stations. The test operations occur in a specified order on the wafer devices, resulting in precedence constraints for the schedule. Furthermore, the assignment of the wafer devices to test stations and the sequence in which they are processed affects the time required to finish the test operations, resulting in sequence dependent setup times. The goal of this research is to develop a realistic model of the semiconductor wafer test scheduling problem and provide heuristics for scheduling the precedence constrained test operations with sequence dependent setup times. A mathematical model is presented and two heuristics are developed to solve the scheduling problem with the objective of minimizing the makespan required to test all wafer devices on a set of test stations. The heuristic approaches generate a sorted list of wafer devices as a dispatching sequence and then schedule the wafer lots on test stations in order of appearance on the list. An experimental analysis and two case studies are presented to validate the proposed solution approaches. In the two case studies, the heuristics are applied to actual data from a semiconductor manufacturing facility. The results of the heuristic approaches are compared to the actual schedule executed in the manufacturing facility. For both the case studies, the proposed solution approaches decreased the makespan by 23-45% compared to the makespan of actual schedule executed in the manufacturing facility. The solution approach developed in this research can be integrated with the planning software of a semiconductor manufacturing facility to improve productivity. / Master of Science

Page generated in 0.0654 seconds