Proposed monolithic triple-junction solar cell structures with the potential for ultrahigh efficiencies using II–VI alloys and silicon substrates

Microstructure of Heteroepitaxial ZnTe Grown by Molecular Beam Epitaxy on Si(211) Substrates

“…Therefore, e k is equal to À12.4%. The array of misfit dislocations reduces the elastic strain by d ¼b Áêh " 111i=d; (2) which is the ratio between the effective Burgers vector and the average distance between two adjacent misfit dislocations, which can be determined from the inverse FFT image (Fig. 2b, c) to be 29.1 Å .…”

“…1 Furthermore, MBE-grown CdTe on Si has proven to be a promising heterostructure for high-efficiency solar cells, which can greatly lower the cost per watt of singleand multijunction solar cells. 2 It is essential to grow ZnTe on As-passivated Si(211) substrates before deposition of CdTe to alleviate the significant lattice mismatch between CdTe and Si, maintain the (211) orientation for the subsequent CdTe growth, and ensure that the surface is terminated with Te (B surface). In addition, it has been demonstrated that thin ZnTe films with about 1 lm thickness can also function very well as a buffer layer for PbSe growth by MBE, because the lattice constant of ZnTe is close to that of PbSe 3 (the lattice mismatch of the two materials is only 0.3% at room temperature).…”

“…Furthermore, ZnTe is also a device layer in recent solar cells based on II-VI semiconductors. 2,10 Knowledge of defects and interface structure is therefore essential for improving device performance. This paper analyzes the interface structure between ZnTe and the Si(211) substrate and discusses the origin of the formation of defects near the interface using high-resolution transmission electron microscopy (HRTEM).…”

Si/ZnxCd1-xTe heterostructures with different Zn contents: growth, electrical and photoelectrical properties

“…Currently, the greatest value of the conversion efficiency of solar energy was received on multijunction structures based on III-V compounds [1]. However, due to a number of technological and economic reasons, the multijunction structures that combine II-VI compounds with silicon are serious competition for the structures based on III-V compounds [2,3]. Among the possible combinations with silicon, of increased interest is a combination of silicon and cadmium telluride -a compound with an optimal set of physical parameters for photoelectric conversion of solar radiation [4].…”

“…The principal limitation in using heterostructures (HS's) of Si/CdTe is a high (~14%) mismatch of lattice parameters of materials. However, the theoretical analysis shows [3] that this problem can be eliminated if, instead of pure CdTe, the Zn x Cd 1-x Te solid solutions are used, for which a misalignment is significantly less.…”