Theoretical study of the maximum power point of n-type and p-type crystalline silicon space solar cells

The performance of crystalline silicon n + / p / p + and n / n / p + solar cells under AM0 spectrum,irradiated with 1 MeV electrons at fluences below 10 17 cm −2 has been analyzed by means ofcomputer simulation. The software used, fully developed by the authors, solves numerically inone dimension under steady-state conditions, the Poisson and continuity equationsself-consistently. The influence of constructive characteristics and different levels of hazardousenvironmental work conditions on the maximum power point of over 150 devices has beeninvestigated. The study has allowed the authors to propose a useful analytical model related tothe constructive characteristics of the device such as polarity, base resistivity and totalthickness, with the aim of examining the electrical performance of Si space solar cells. Resultspresented in this paper are important in order to contribute to the design of radiation-hardeneddevices. 1. Introduction Taking into account the urgent need to make the most ofalternative energy sources, the study of semiconductor devicesthatcanprovidepoweratlowoperatingcost,suchassolarcells,is extremely important at the present time. Deep studies aboutso-calledthirdgenerationsolarcells,focusedonnewmaterialsand technologies such as intermediate band, quantum dots andhot-carrier devices [1–4], are being carried out with the aimof reducing the cost and increasing the efficiency with respectto the first generation, i.e. crystalline silicon (c-Si) solar cells.However, in present times a considerable amount of researchin the field of the photovoltaic cells is still dominated by theconventional c-Si devices.For space power applications, where the devices areexposed to irradiation of high energy particles, multijunction(MJ) solar cells based on III–V technologies havedemonstrated higher conversion efficiencies and radiation-resistance than c-Si devices [5–7]. Nevertheless, c-Si solarcells have proven to offer a worthy operational reliability andcosteffectivenessasaspacepowersource[8–10]andthereforefurther research in this topic is still required.Every different solar cell structure from a given material,total thickness, base resistivity and polarity (p- or n-type),is expected to respond differently as a function of radiation.Therefore, each device must undergo some kind of irradiationtest to determine the degradation characteristics. Nowadays,precise techniques of modeling and simulation have becomefundamental tools to predict and to improve the responseof electronic devices under different operation conditions,offering valuable knowledge at a much lower cost and in lesstime than experimentation.In order to contribute to the design of radiation-hardeneddevices, this paper presents a theoretical study of the behaviorof different c-Si n