• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • Tagged with
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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.
1

Thermionic Emission Diffusion Model of InP-based Pnp Heterojunction Bipolar Transistor with Non-Uniform Base Doping

VUMMIDI MURALI, KRISHNA PRASAD 02 September 2003 (has links)
No description available.
2

The development of a novel all ternary InAlAs/InGaAs double heterojunction bipolar transistor (DHBT) for the design, simulation and fabrication of a static divide-by-2 frequency divider

Knight, Robert John January 2012 (has links)
The research focused on evaluating the feasibility into Microwave Monolithic Integrated Circuits (MMIC) fabrication capability, in the UK, using novel material type: all ternary In0.52Al0.48As/In0.53Ga0.47As lattice matched to InP substrate double heterojunction bipolar transistor (DHBT) technology; with the potential for providing high speed HBTs. The demonstration of a MMIC capability would follow with the development of a BiFET process that would satisfy SELEX Galileo circuit business needs. The research project complexity is divide into 5 phases: phase 1, the development of a high frequency In0.52Al0.48As / In0.53Ga0.47As lattice matched to InP substrate DHBT technology; phase 2, development of passive components; phase 3, the creation of two VBIC physical models; phase 4, the creation of a Process Development Kit (PDK) and phase 5, the design, simulation and fabrication of a divide-by-2 frequency divider using the technology developed in phase 1. Phase 1, concluded with a DHBT epitaxial design and fabrication that produced devices with a peak high frequency performance f_t = 140GHz and f_max = 95GHz at a current density Jc ≈ 1mA/µm2. This was achieved through the optimisation of the epitaxial design to reduce the base transit time τb through the introduction of a quasi electric field and thinning of base layer. To the best of the author’s knowledge, this is the highest f_t performance for a 1µm emitter width all ternary In0.52Al0.48As / In0.53Ga0.47As DHBT. The design, simulation and fabrication of a divide-by-2 frequency divider were only made possible by the successfully development of passive components (phase 2) and the VBIC model and PDK creation (phase 3 and 4). The divide-by-2 frequency divider design and simulation was done via the use of the PDK. The simulations resulted in a divide-by-2 frequency divider with a maximum operating frequency of 27GHz at a minimum input power of 2dBm. The fabrication of the MMIC resulted in a transistor component yield of 69%, which unfortunately resulted in a divide-by-2 frequency divider circuit yield of 0%. The fabrication of MMIC circuits is not possible with current state of the fabrication environment; however the only obstacle the University of Manchester (UoM) faces is low active component yield. To increase the active component yield to the 95% level required for high circuit yields, large capital investment into the fabrication equipment and human time into setting up the fabrication process to a repeatable and reliable standard is required.

Page generated in 0.0176 seconds