Mechanically Stacked Transmissive Solar Cells for Broader Spectrum Capture

The solar energy conversion system is divided into multiple separate layers, each with different bandgap energies. The first layer captures high-energy photons (ultraviolet and visible light), while the second layer captures lower-energy photons (visible and infrared light). This segmentation allows each layer to specialize in converting specific portions of the solar spectrum, thereby increasing overall power conversion efficiency beyond the 25% limit of conventional single-layer cells.

The invention transitions from a conventional single-plane solar cell to a vertically stacked multi-layer configuration. By adding the dimension of vertical layering with different bandgaps, the system can simultaneously capture photons across a broader spectrum range, converting both high-energy and low-energy photons that would otherwise be lost in a single-layer system.

The manufacturing process is segmented into separate steps for producing each layer with its specific bandgap material. This allows each layer to be optimized and manufactured independently using established photovoltaic manufacturing techniques, making the multi-layer system more manufacturable than a monolithic multi-junction cell while still achieving enhanced efficiency.

The patent introduces an intermediary transparent conductive oxide layer between the first and second solar cell layers. This intermediary layer serves multiple functions: it provides electrical connection between layers, maintains mechanical stability of the stack, and allows optical transmission. The use of standard transparent conductive oxides in existing manufacturing processes facilitates the integration of multiple layers without requiring entirely new manufacturing methodologies.