Research Proposal Dissertation Example | Topics and Well Written Essays - 1750 words

Research Proposal - Dissertation Example Solar energy, if harnessed to its fullest, can provide the whole world with more than enough energy for a year, in just a single day. Science and technology is still far from that point. Solar energy harnessing with today’s inventions is still expensive and inefficient, making this a very exploitable research field, with the promise of a better world. Solar energy will soon come out as a multibillion dollar industry, and only those nations will prosper through it, which spend time, efforts and money in this field today. Solar energy harnessing through photovoltaic cells is a very promising field. To enhance the efficiency, increasingly thin films are being prepared. PVs are made out of doped semiconducting materials, which have relatively high resistivity as compared to common good conductors. Thus, photovoltaic cells are coated with conducting materials on their surface. These are thin films themselves, whose sole purpose is to behave as a conducting medium. The coatings are done over the photovoltaic layers, such that they are present between the light source and the photovoltaic layer. This means that the coatings have to be highly transparent for light transmission as well. The materials employed for this purpose are termed as Transparent Conducting Oxides, which are nothing but doped oxides that have very high conductivity and transmission. TCOs may have a variety of functions, such as transparent electrical contacts, antireflection coatings and chemical barriers, in photovoltaic films (Perkins et. al. 20051). It is to be noted that the energy band gap theory suggests that transparency of a material is closely related to the electrical behavior of a material, more specifically its resistivity. Transparency of a material is higher if the band gap between the valence and conduction band is high. If the band gap is high, the resistivity is high too. Thus it is difficult to have both high transparency and low resistivity together. To achieve this, dopin g is done in selected semiconductors, which can modify their properties to give us transparent layers with high conduction (Nave, 20102). A lot of research has been done in this field for over 50 years now and every project has led to the opening of a new chapter rather than closing out different chapters in the research. This is suggestive of the prospects of research in this field. The most important property of TCOs is their conductivity, and a lot of research has been done on that (Minami, 20003; Lewis and Paine, 20004) on aluminum doped zinc oxide, tin doped indium oxide, lead oxides, cadmium oxides, and their combinational oxides. These researches have indicated that there exists potential for engineered transparent conducting oxides to be formed with tailored properties (Freeman et. al. 20015). Transparency and light trapping has also been studied in detail in these papers. The main emphasis of the researches is to study composition-property behaviors. Some endeavors have als o been made for synthesis and characterization of these thin films (Banarjee et. al. 20036; Coutts and Young, 20007; Gurumurugan et. al. 19948; Freeman et. al. 2001). Researchers have also used surface characterization techniques to study how electrical, chemical and transparency properties of TCOs depend on the surface layer. The electronic/defect structure of the surface layers has a huge impact on the electrical properties of the layer