CdTe-based double heterostructures and related light-conversion devices

摘要

Devices converting light to electricity (such as solar cells or photodetectors) including a heavily-doped p-type a-SiC_y:H and an i-Mg_xCd_1-xTe/n-CdTe/N—Mg_0.24Cd_0.76Te double heterostructure (DH), with power conversion efficiency of as high as 17%, V_oc as high as 1.096 V, and all operational characteristics being substantially better than those of monocrystalline solar cells known to-date. The a-SiC_y:H layer is configured to enable high built-in potential while, at the same time, allowing the doped absorber to maintain a very long carry lifetime. In comparison, similar undoped CdTe/Mg_xCd_1-xTe DH designs reveal a long carrier lifetime of 3.6 μs and an interface recommendation velocity of 1.2 cm/s, which are lower than the record values reported for GaAs/Al_0.5Ga_0.5As (18 cm/s) and GaAs/Ga_0.5In_0.5P (1.5 cm/s) DHs.