High-Efficiency Perovskite Solar Cells with Sputtered Metal Contacts

Area of Science:

• Materials Science
• Renewable Energy
• Device Physics

Background:

• Sputter deposition offers advantages for creating scalable metal contacts in perovskite solar cells (PSCs).
• However, the sputter deposition process can induce damage to sensitive underlying layers within the PSC structure.

Purpose of the Study:

• To investigate if post-sputtering aerial oxidation can mitigate or reverse the damage caused by sputter deposition of metal contacts in PSCs.
• To compare the performance and stability of PSCs fabricated with sputtered gold (Au) contacts treated with oxidation against those with thermally evaporated Au contacts.

Main Methods:

• Fabrication of perovskite solar cells (PSCs) using sputter deposition for gold (Au) metal contacts.
• Application of a post-sputtering aerial oxidation step to specific PSCs.
• Characterization of device performance (efficiency) and stability.
• Analysis of the molecular order and atomic diffusion within the hole transport layer (HTL) using experimental techniques.

Main Results:

• PSCs with sputtered Au contacts, followed by aerial oxidation, achieved higher power conversion efficiencies (18.7%) compared to those with thermally evaporated Au contacts (18.4%).
• The post-sputtering oxidation step was shown to reconstruct the molecular order of the hole transport layer (HTL).
• Oxidation effectively reversed the diffusion of Au atoms into the HTL, a detrimental effect of sputtering.

Conclusions:

• Post-sputtering aerial oxidation is a viable method to repair sputter-induced damage in PSCs, enhancing device performance.
• This oxidation step restores the HTL's molecular integrity and prevents metal diffusion, previously overlooked in fabrication.
• The findings are significant for the scalable manufacturing of high-quality perovskite solar cells using sputtering techniques.