Research Center for Photovoltaics, National Institute of Advanced Industrial Science and Technology , 1-1-1 Umezono, Tsukuba 305-8568, Japan.
ACS Appl Mater Interfaces. 2017 Sep 6;9(35):29677-29686. doi: 10.1021/acsami.7b07092. Epub 2017 Aug 22.
Amorphous (a-) InO-based front contact layers composed of transparent conducting oxide (TCO) and transparent oxide semiconductor (TOS) layers were proved to be effective in enhancing the short-circuit current density (J) of Cu(In,Ga)Se (CIGS) solar cells with a glass/Mo/CIGS/CdS/TOS/TCO structure, while maintaining high fill factor (FF) and open-circuit voltage (V). An n-type a-In-Ga-Zn-O layer was introduced between the CdS and TCO layers. Unlike unintentionally doped ZnO broadly used as TOS layers in CIGS solar cells, the grain-boundary(GB)-free amorphous structure of the a-In-Ga-Zn-O layers allowed high electron mobility with superior control over the carrier density (N). High FF and V values were achieved in solar cells containing a-In-Ga-Zn-O layers with N values broadly ranging from 2 × 10 to 3 × 10 cm. The decrease in FF and V produced by the electronic inhomogeneity of solar cells was mitigated by controlling the series resistance within the TOS layer of CIGS solar cells. In addition, a-InO:H and a-In-Zn-O layers exhibited higher electron mobilities than the ZnO:Al layers conventionally used as TCO layers in CIGS solar cells. The InO-based layers exhibited lower free carrier absorption while maintaining similar sheet resistance than ZnO:Al. The TCO and TOS materials and their combinations did not significantly change the V of the CIGS solar cells and the mini-modules.
由透明导电氧化物 (TCO) 和透明氧化物半导体 (TOS) 层组成的非晶(a-)InO 基前接触层被证明可以有效地提高玻璃/Mo/CIGS/CdS/TOS/TCO 结构的 Cu(In,Ga)Se(CIGS) 太阳能电池的短路电流密度 (J)，同时保持高填充因子 (FF) 和开路电压 (V)。在 CdS 和 TCO 层之间引入了 n 型 a-In-Ga-Zn-O 层。与广泛用作 CIGS 太阳能电池中 TOS 层的本征掺杂 ZnO 不同，a-In-Ga-Zn-O 层的无晶界 (GB) 非晶结构允许具有更高电子迁移率，并且对载流子密度 (N) 具有更好的控制。在含有 a-In-Ga-Zn-O 层的太阳能电池中，N 值广泛在 2×10 到 3×10 cm 之间，实现了高 FF 和 V 值。通过控制 CIGS 太阳能电池 TOS 层中的串联电阻，可以减轻由太阳能电池的电子非均匀性引起的 FF 和 V 的降低。此外，a-InO:H 和 a-In-Zn-O 层的电子迁移率高于传统用作 CIGS 太阳能电池中 TCO 层的 ZnO:Al 层。InO 基层在保持与 ZnO:Al 相似的薄层电阻的同时，表现出更低的自由载流子吸收。TCO 和 TOS 材料及其组合并没有显著改变 CIGS 太阳能电池和微型模块的 V 值。
