On the application of hole‐selective MoO_x as full‐area rear contact for industrial scale p‐type c‐Si solar cells

Abstract

We present the feasibility of integrating substoichiometric molybdenum oxide (MoOx) as hole‐selective rear contact into the production sequence of industrial scale p‐type crystalline silicon (c‐Si) solar cells. Thin films of MoOx are deposited directly on p‐type c‐Si by thermal evaporation at room temperature. It is found that Ag/MoOx/p‐type c‐Si rear contact structure exhibits low contact resistivity and modest surface recombination current density. The attained peak efficiency (η) of the fabricated solar cells is 17.65% with Voc of 626 mV, Jsc of 36.8 mA/cm2, and fill factor (FF) of 76.63%. Next, a complete loss analysis of a MoOx/p‐type Si heterojunction solar cell is carried out for the first time by using Quokka simulation software that employs characteristics of different layers which constitute the fabricated solar cell. Based on this loss analysis, the dominant loss mechanisms are defined and a roadmap to attain the desired highest possible efficiency from industrial scale p‐type c‐Si solar cells with full‐area MoOx hole‐collecting rear contact is explored.

Cerous Fluoride Dopant‐Free Electron‐Selective Contact for Crystalline Silicon Solar Cells

“…The 0.8-1 nm SiO x layer is typically formed by native oxidation during the process of the sample transfer and long-time vacuuming before thermal evaporation. [29,30] Synchronously, EDX maps of the CeF 3 /Al/c-Si(n) contact with a 10 nm resolution are displayed in Figure 3b. The Al, Ce, F, O, and Si elemental signals confirmed the presence of the CeF x and SiO x layers.…”

Electrophoretic Codeposition of MoOx/MoS2 Thin Film for Platinum-Free Counter Electrode in Quantum Dot Solar Cells

“…Moreover, according to prior studies, the electrocatalytic activity of MoS 2 in the thin film was positively influenced by the appearance of molybdenum oxides (MoO x ), as a layer of substoichiometric molybdenum oxide (MoO x , 2 < x < 3) and other n-type transition metal oxides (TMOs) can be used as a Hole Extraction Layer (HEL) to improve the performance of the QDSCs [50]. MoO 3 , which was normally an insulator, was transformed into the oxygen-deficient species of MoO x and MoO 2 due to surface passivation via the bonding between FTO silicon and TMO oxygen when the thickness was sufficient [51][52][53]. This MoO x passivation layer could behave like a barrier for the interfacial recombination, thus could improve the photoelectrochemical performance of the thin films.…”

Fourteen percent efficiency ultrathin silicon solar cells with improved infrared light management enabled by hole‐selective transition metal oxide full‐area rear passivating contacts

“…The thickness, optical characteristics, and band gap of the deposited TMO layers were extracted using variable angle spectroscopic ellipsometry (VASE‐ Semilab‐GES5E) by utilizing the appropriate dispersion model to fit the measured data 50–53 . Excess carrier lifetime (τ) of each TMO/p‐Si and corresponding rear contact recombination parameters ( J 0 rear ≈ J 0 rear contact 54,55 ) were measured from symmetrically TMO coated DSP c‐Si by using Sinton Instruments WCT120 photoconductance decay measurement tool according to Kane and Swanson technique 56 . The contribution of TMO/p‐Si single surface ( J 0 rear contact ) was calculated by dividing the total measured J 0 of the TMO/p‐Si/TMO by two.…”