Effect ofPhosphorous Dopant Concentration on Resistivity of Crystalline Silicon

Zena, Yohannes

dc.contributor.author	Zena, Yohannes
dc.date.accessioned	2017-07-31T10:52:12Z
dc.date.accessioned	2017-07-31T10:53:08Z
dc.date.available	2017-07-31T10:52:12Z
dc.date.available	2017-07-31T10:53:08Z
dc.date.issued	2017-07-31
dc.identifier.uri	http://hdl.handle.net/123456789/7491
dc.description	A Thesis Submitted to the Department ofMaterials Science & Engineering for the Presented in Partial Fulfillment ofthe Requirements for the Degree ofMaster of Science in Materials Science & Engineering	en_US
dc.description.abstract	Abstract This study investigates the effects of phosphorus dopant concentration on the resistivity of crystalline silicon (c-Si). The study considers different level doping concentration and temperature variation in relation to its effect on the resistivity ofthe material. This research work is based on simulation based study by using existing software called "Resistivity Calculator" from a source called PV Light House. The resistivity of the crystalline silicon as a function of dopant concentration and temperature are calculated using the software and thereafter the raw data is plotted using origin software. The change of parameters for the concentration and temperature are within the range of 10 12 cm- 3 up to 10 20 cm- 3 and 100 K up to 500 K, respectively. The study indicated that the resistivity of phosphorous-doped silicon, at different temperature, tends to decline as doping concentration is increased. Such an effect is attributed to increased number of charge carriers by doping. On the other hand, the resistivity of the doped semiconductor, at different doping concentration, showed different trend as the temperature increases, where it can be seen in three categories: I) resistivity increased and then decreased, after 400 K, for doping concentrations 10 increases for doping concentrations 10 13 15 to 10 to 10 14 16 cm- cm- 3 , II) resistivity increased as temperature 3 , and Ill) resistivity not significantly affected, almost linear, by increasing the temperature for high doping concentration 10 cm- " " 3 • This seems to indicate that the lattice scattering (r 3 / 2 ) versus impurity scattering (T both affected by temperature differently, are dominating one another depending the doping concentration and thus contributed to resistivity/conduction in different trend. Here, it worth mentioning that, it is related to the existing theory of mobility as a function of temperature at different doping concentration, and the study indicated the effect of doping on the electrical parameters of the material quantitatively. Based on the study, at high dopant concentration (above I 0 15 cm- 3 ) the effect of temperature is negligible as the temperature dependence of resistivity is dominated by lattice scattering; and the concentration of impurity ions and thermally exited ions cancel out each and as result resistivity becomes almost constant, i.e., the rate of change of resistivity is constant. On the other hand, at low doping concentration lattice scattering dominates the rate of change of resistivity increase with temperature.	en_US
dc.subject	MATERIALS SCIENCES AND ENGINEERING	en_US
dc.title	Effect ofPhosphorous Dopant Concentration on Resistivity of Crystalline Silicon	en_US
dc.type	Thesis	en_US