(a) You need to dope Si to produce free positive charge carriers. (1) Explain how this...
(a) You need to dope Si to produce free positive charge carriers. (i) Explain how this process will be achieved by sketching a 2D representation of the Si crystal lattice to show the effect of this doping process. Clearly explain what impurities you will use for this process. (3)
(ii) Sketch the energy band diagram of this doped material in (i) at 0 K and identify all the important features in your diagram. (3) (iii) Now sketch the same energy band diagram as in (i) but at a temperature of 300 K. Again, label all the important features in your diagram. (3)
(iv) Explain what process(es) will be different at the higher temperature producing the different features from (ii) to (iii). (2) (b) A structure that we sometimes encounter in electronic devices is a so-called p-i-n structure, consisting of a p-doped layer, an intrinsic layer and then an n-doped layer as shown in the drawing below. Assume Si as the semiconductor: P US- [Intrinsic 5 XION n kx 10 cm Assume a temperature of 300 K and with the doping as indicated...
Taking pure silicon (Si) as an example, explain what is meant by the terms electron-hole generation and recombination, how they affect the electrical conductivity, and define what is meant by the "intrinsic carrier density", n. [5 marks] Q3. a) b) With the aid of both lattice and energy band diagrams, explain how n-type doping of Si is achieved and state two types of suitable dopant atoms. [7 marks] c) An n-type region on a Si wafer has a donor concentration...
EENG 245 Physical electronics HW 1 1) The NaCl crystal is cubic, and can be described as follows. Na atoms sit at the corners and faces of a cube, and Cl atoms sit in between two Na atoms. This means that a Clatom is found half-way along each of the cube edges, and there is a Cl in the center of the cube. (We could also have described the lattice by interchanging Na and Cl in the description above.) Another...
1. According to the paper, what does lactate dehydrogenase (LDH) do and what does it allow to happen within the myofiber? (5 points) 2. According to the paper, what is the major disadvantage of relying on glycolysis during high-intensity exercise? (5 points) 3. Using Figure 1 in the paper, briefly describe the different sources of ATP production at 50% versus 90% AND explain whether you believe this depiction of ATP production applies to a Type IIX myofiber in a human....