Preparation of Semiconducting Thin Films

Beran, J. A. Laboratory Manual for Principles of General Chemistry. 8th ed. Hoboken, NJ: John Wiley & Sons, Inc.; 2009

Insulator – Do not allow electric charges to pass through them. Electrons in the atoms and molecules move very slightly to one side of the object but are not released.

Through doping, it creates two groups of semiconductors, N-type, which have a negative charge and P-type, which have a positive charge. These different types of semiconductors are very important to the world, because when the different types are used together they can create devices with special electrical devices that have the ability to control electrical signals. Before semiconductors there were vacuum tubes, which did the same job as semiconductors, but they were not as fast or as small as them. Vacuum tubes, however, are very rugged and durable they can go through temporary overload conditions.

Scherrer equation, as shown in equation 1, was applied to estimate the average crystallite size of these sulfurized films.

Not all materials are created equal in terms of their conductive ability. Some materials are better conductors than others and offer less resistance to the flow of charge. Silver is one of the best conductors, but is never used in wires of household circuits due to its cost. Copper and aluminum are among the least expensive materials with suitable conducting ability to permit their use in wires of household circuits. The conducting ability of a material is often indicated by its resistivity. The resistivity of a material is dependent upon the material's electronic structure and its temperature. For most (but not all) materials, resistivity increases with increasing temperature. The table below lists resistivity values for various materials at temperatures of 20 degrees Celsius.

Since the perovskites are direct-gap semiconductors [1], we plot 〖α(E)〗^2 E^2 as a function of photon energy, E, in Fig. S2(a) where α(E) is obtained by subtracting the

Conductive polymers are a specific section under the broad range of polymers, that have the ability to effectively conduct electricity. They were discovered by accident in a lab by Hideki Shirakawa in 1974, yet their potential applications were not understood until early 2000s. They are made by doping with n-type and p-type which forces electrons to move throughout the material which normally would not happen because of a polymer molecular structure. They provide many advantages over metals because of they are light weight, cheap, and functional versatile. Conductive polymers are frequently used with rechargeable batteries, sensors, and light displays. Lastly, they have a bright future with the world turning towards wanting more technology that is light weight and integrated in the day-to-day functions.

My interest in these fields will require an extensive academic and research foundation regarding devices that rely heavily on quantum, electromagnetic and other phenomena. It will also require me to initially focus my efforts before exploring a breadth of other fields and applications that will become an integral part of my research repertoire. My academic interests and career objectives span both theoretical and practice-based branches of learning. I have seen how many factors in epitaxial growth of groups III and V semiconductor materials may render a great theoretical design difficult to realize. The challenges in solving and computing for several equations and in reaching a trade-off in designs also need to prove viability. This is only obtainable through a deep understanding

LIGHT: shining light into semiconductor increasing the conductivity of the materials. from this property we could use semiconductor materials in (light detector)

More detailed effects from sulfurization and cobalt doping could be observed from band gap calculation and analysis. The direct band gap energy was estimated through plotting (αhυ)2 versus energy hυ. Corresponding

Due to the structurally stable band gap of 2D TMDs, they can be used in the fabrication of transistors. In 2004, the first transistor made from 2D TMDs (WSe2) was published with a mobility of less than 500cm2v-1s-1 for p-type conductivity which is about half of that of silicon based transistors and it had a low on/off ratio which was due to the fabrication of this device on a bulk material. However, MoS2 is a better option for transistor applications because of its higher on/off ration exceeding 108 and mobility. Due to the bandgap of TMD monolayers being in the visible range(400nm-700nm), they have a higher efficiency and are very promising for optoelectronic applications. MoS2 has been used to

Although the idea of luminescent SiCN structure was initiated in a previous master project where the ICPCVD system was employed, the parameters to fabricate luminescent SiCN thin films have not been established by the time of starting this thesis. Therefore, first, it was required to calibrate the deposition parameters to find the composition of the SiCN films exhibited luminescent. This involves a significant number of film depositions, the system maintained and troubleshooting of the plasma-assisted ultra-high vacuum deposition systems as well as some multitude characterization techniques. The results of this work have been accepted to publish in “Thin Solid Films” journal (#4) and were presented at the 211th Meeting of the

Gallium nitride (GaN) is a binary III/V direct bandgap semiconductor with a bandgap of 3.4 eV commonly used in light-emitting diodes since the 1990s. GaN has a low sensitivity to ionizing radiation which makes it a suitable material for solar panels on satellites. Various military and space application also benefit from the usage if this radiation hardened material. Besides the wide bandgap, high breakdown field and high saturation velocity of GaN make it very promising for high power, high-speed and high temperature electronic devices. GaN devices offer five key characteristics: high dielectric strength, high operating temperature, high current density, high speed switching and low on-resistance. These characteristics are due to the properties of GaN, which, compared to silicon, offers ten times higher electrical breakdown characteristics, three times the bandgap, and exceptional carrier mobility. Low resistance Ohmic contacts with a smooth morphology, and good edge acuity and thermal stability are imperative in the successful implementation of all these devices, particularly high power devices

Indium is known to have an acceptor level which is 156 meV above the top of the valence band of silicon. As a result, the fraction of ionized indium atoms increases with temperature, resulting in reduced gain.

Now we will move onto other materials that are involved with electronics. The next group of materials that will be discussed are insulators. An insulator is a material that does not conduct electricity at all but will resist or stop it from traveling further. An insulating atom has eight electrons in its valance shell which makes this shell complete. Eight is the most electrons that any atoms can have in their valance shell this is why these are called insulators, no more electrons can fit in the valance shell of these atoms.