Rear-Contact Silicon Thin-Film Solar Cell

Simple SummaryContent extracted from patent full text and abstract with AI.

The patent describes a back-contacted silicon thin-film solar cell that is built on a glass substrate. The core innovation lies in the specific layer design, including a barrier layer to prevent contamination, optical enhancement layers, a thin silicon/oxygen-containing layer, and a crystalline n-type silicon absorber made via liquid-phase crystallization. The resulting structure features a highly passivated interface and monocrystalline silicon grains for improved electron transport. This design achieves higher open-circuit voltages and better efficiency than previous thin-film silicon solar cells.

Use CasesContent extracted from patent full text and abstract with AI.

• Rooftop solar panels for homes and commercial buildings
• Integration into building facades or windows (building-integrated photovoltaics)
• Portable solar power devices
• Large-scale solar farms and power plants
• Solar-powered consumer electronics where efficient, thin, and low-cost cells are needed

BenefitsContent extracted from patent full text and abstract with AI.

• Higher efficiency due to reduced recombination and improved charge collection
• Reduced shading losses because all electrical contacts are on the back side
• Low-cost manufacturing by using thin silicon layers and glass substrates
• Lower material consumption compared to traditional wafer-based cells
• Potentially higher open-circuit voltages (>625 mV)
• Improved long-term stability due to effective barrier and passivation layers
• Enables flexible designs and integration with various surfaces due to thin-film approach

Technical Classifications (CPCs)

Inventors & Applicants

Patent Abstract

The invention relates to a back-contact Si thin-film solar cell, at least comprising a crystalline Si absorber layer and an emitter layer arranged on the crystalline Si absorber layer, the absorber layer and the emitter layer being composed of semiconductor materials of opposite p- and n-type doping, wherein a barrier layer is formed on a glass substrate, which barrier layer has a layer thickness in the range of 50 nm to 1 μm, at least one layer that improves the optical properties and that has a layer thickness of 40 nm to 250 nm is arranged on the barrier layer, on which at least one layer that improves the optical properties a 0.5 nm to 20 nm thin layer containing silicon and/or oxygen is arranged, wherein the crystalline Si absorber layer can be produced by means of liquid-phase crystallization and is n-conducting, has a layer thickness between 200 nm and 40 μm with homogenous doping between 2 ⋅ 1015 cm-3 to 5 ⋅ 1018 cm-3 over the entire thickness, and has monocrystalline Si grains, which are at least as large in the extent thereof as the thickness of the absorber layer, and an SiO2 passivation layer is formed between the layer containing silicon and/or oxygen and the Si absorber layer during the liquid-phase crystallization.