The operation of the semiconductor-insulator-semiconductor (SIS) solar cell: Theory

Abstract

Recently 12% efficient indium tin oxide (ITO) on silicon solar cells have been reported. Experiments indicate the presence of a thin interfacial insulating layer. Thus, these devices appear to belong to a class of semiconductor-insulator-semiconductor (SIS) solar cells where one of the semiconductors is a degenerate wide-band-gap oxide. We have developed a theory in terms of minority-carrier tunnel current transport through the interfacial layer where one semiconductor is in a nonequilibrium mode. The wide-band-gap semiconductor serves to block band-to-band majority-carrier current and thus, in principle, give better device performance than with an MIS solar cell. The effects of interfacial layer thickness, substrate doping level, surface states and interface charge, temperature on the performance of SIS solar cells have been calculated. These indicate that real-world ITO on silicon cells should be able to achieve 20% efficiency under AMl illumination. Other combinations of semiconductors would yield even better performance.

Electronic Current Transport through Molecular Monolayers: Comparison between Hg/Alkoxy and Alkyl Monolayer/Si(100) Junctions

“…[14,23] For semiconductor/molecular monolayer/metal junctions, electronic current transport measurements were found to provide the clearest indication of monolayer quality, in particular if series of monolayers were used, each composed of molecules of different lengths, where transport across the junction is via thermionic emission, tunneling, or a mix of these two mechanisms. [14][15][16] However, until now only isolated electronic current transport data with alkoxy monolayers were reported. [17] Here we investigate and compare junctions made with sets of molecules of different lengths, bound via either Si-O-C or Si-C bonds to the substrate.…”

Atomic layer deposition precursor step repetition and surface plasma pretreatment influence on semiconductor–insulator–semiconductor heterojunction solar cell

“…That also implies worse initial growth behavior. Theoretical calculations of Shewchun et al 17 on the behavior of J sc related to dielectric layer thickness demonstrate also this strongly decrease after exceeding a thickness limit (1.8 nm for SiO 2 ). During the O 2 plasma pretreatment step of (4) O 2 and H 2 plasma a SiO x layer with an equivalent thickness of 2 cycles Al 2 O 3 was generated.…”

“…Semiconductor-insulator-semiconductor (SIS) is also a type of heterojunction, which was first developed in the 1970s and achieves theoretically a maximum conversion efficiency of 25%. [17][18][19] A SIS junction consists of two semiconductors that are separated by a 1-3 nm thin dielectric layer. The charge carrier separation mechanism bases on a quantum mechanical tunneling of charge carriers through the dielectric barrier.…”

Solar Cells on the Base of Semiconductor-Insulator-Semiconductor Structures

“…ITO/nSi SC with the power conversion efficiencies of 10% were fabricated by deposition onto n-type Si crystals by the electron-beam evaporation of a mixture of 90:10 molar % In 2 O 3 : SnO 2 powder (Feng et al, 1979). The results of those works have been analyzed in detail (Shewchun et al, 1978; from both experimental and theoretical points of view. Given the general theory of heterojunctions is incomprehensible, how they can work as effective SC formed by materials with different crystalline types and lattice constants, when an intermediate layer with many defects appears at the interface.…”

“…A overview on this subject was presented in (Malik et al, 2009). Basic investigations of the ITO/Si SIS structures have been carried out and published in the USA (DuBow et al, 1976;Mizrah et al, 1976;Shewchun et al, 1978; Theoretical and experimental aspects of the processes that take place in these structures are examined in those papers. Later on the investigations of SC based on SIS structures using, as an absorber component, Si, InP and other semiconductor materials have been continued in Japan (Nagatomo et al, 1982;Kobayashi, et al, 1991), India (Vasu & Subrahmanyam, 1992;Vasu et al, 1993), France (Manifacier & Szepessy, 1977;Caldererer et al, 1979), Ukraine (Malik et al, 1979;Malik et al, 1980), Russia (Untila et al, 1998), the USA (Shewchun et al, 1980;Gessert et al, 1990;Gessert et al, 1991), Brasil (Marques & Chambouleyron, 1986) and the Republic of Moldova (Adeeb et al, 1987;Botnariuc et al, 1990;Gagara et al, 1996;Simashkevich et al, 1999).…”