الفهرس 
ContentsOnly 14 pages are availabe for public view
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Abstract
The importance of energy in our society has become all too parent in recent years. Of the various energy alternatives, energy has the very desirable property of being essent¬limitless and without the problems of pollution or physic- danger.
A solar cell is a photovoltaic device designed to convert br>. unlight into electrical power and to deliver this power into ’a suitable load in an efficient manner. There are 800 satel¬lites of various types in orbit around the earth, powered to br>a very large degree by silicon solar cells, and it is safe to [.say that without these cells, we would not have the sophisticat¬ed weather, communications, military, and-s’cientific satellite capabilities we have to day. The adv-antages of solar cells lie ability to provide nearly permanent, uninterrupted
no operating cost with only heat as a waste product, and their conversion of light directly into electricity rather some intermediate form of energy. They also have a high power/ weight ratio compared to other power sources. Their chief dis¬advantages lie in the low power/unit area of sunlight, their relatively low efficiency, and the degradation that takes place in hostile high energy particle environments. br>As useful as solar cells have been in the space program, their potential -importance for large scale power generation to meet earth’s energy needs is even greater. A few years ago, very Few people would have seriously proposed solar energy as a major power source
; fossil fuel burning, s~e~m powered generatior. plants
were cheap and fuel supplies seemed inexhaustible. Today, how- ever, the rising price of fuel, the realization that oil and gas can only last a relatively few decades,- and the freedom energy from pollution, have all led to closer looks atan alternative to present day fossil fuel system~. There are several physical mechanisms responsible for the ecrease of the efficiency of a solar cell. One of them are series
resistances. The major contributors to the series resist- are the bulk resistance of the se~iconductor material the cell, the bulk resistance of the metallic contacts and interconnections, and the contact resistance between the metallic contacts and the semiconductor. The shunt resistance, is caused by leakage across the p-n ’junction around the edge SH of the cell and in non-peripheral regions in the presence of crystal defects and precipitates of foregin impurities in the junction region.
The present work gives a solution for the resistance of the <top layer of a photovoltaic cell using Poisson’s equation numerical solution, the boundary conditions of the side of the slab facing the depletion layer is determined using a distributed model for the photovoltaic cell. It is found out that the effect of series resistance is sensitive to the doping profile. It also affects the efficiency only at high light concentration •