Skip to content
Earth Energy Log
solar

HJT

Also known as: Heterojunction Technology, HIT

Solar cell technology combining crystalline and amorphous silicon layers, offering higher efficiency at higher capex than TOPCon.

HJT (Heterojunction Technology) combines monocrystalline silicon with thin amorphous silicon layers, achieving very low surface recombination losses. Mass-production efficiency averages 25.9% — slightly higher than TOPCon. HJT historically carried a capex premium, but silver paste reduction and indium-free TCO have closed the gap in 2025–2026.

Related terms

  • TOPCon Solar cell architecture using a tunnel oxide layer to passivate rear contacts —
  • PERC Legacy crystalline silicon cell architecture that dominated solar from 2018–2023
  • Back-Contact Cell Solar cell with all electrical contacts on the rear, eliminating front-side shad