Phosphorus silicon glass layer photovoltaic

What is the phosphosilicate glass layer?

Commonly, the dopant source grown on the silicon surface during the deposition step of POCl 3 diffusions is referred to as the phosphosilicate glass (PSG) layer. Actually, the PSG layer is separated from the silicon surface by a thin silicon dioxide (SiO 2 ) layer featuring a much lower phosphorus concentration [2].

What is phosphosilicate glass (PSG) layer system?

The phosphosilicate glass (PSG) layer system grown on the silicon surface during diffusion processes with phosphorus oxychloride (POCl 3) is a two-layer stack system consisting of a PSG and a silicon dioxide (SiO 2) layer. Understanding the stack layers’ structure and composition is essential for further optimizing POCl 3 diffusion processes.

How do phosphorus silicate glass layers affect PV efficiencies?

Phosphorous silicate glass (PSG) layers were carefully designed on an emitter layer to determine how they affect the efficiencies of solar cells before and after PID. A current-voltage (I-V) tester was used to determine PV parameters. An ellipseometer and transmission electron microscope (TEM) were used to measure the thicknesses of the PSG layers.

Why is phosphorus oxychloride used in photovoltaics?

The diffusion of phosphorus mediated by phosphorus oxychloride (POCl_3) is extensively used in photovoltaics due to its enhanced diffusion speed and to the high controllability of the phosphorus at the wafer surface.

How is phosphosilicate glass formed?

A common P diffusion method is to expose Si wafers in a furnace at about 800–900 °C to an atmosphere of POCl 3 and O 2 (with N 2 as a carrier gas), forming a phosphosilicate glass (PSG) on the wafer surfaces. This process step is usually called pre-deposition, and the resulting PSG provides a source of P dopants that diffuse into the Si wafer.

Where is phosphosilicate glass used?

Present address: Global Photovoltaic Simulation Group, Case Postale 1056, 1211 Geneva 1, Switzerland. The phosphosilicate glass (PSG), fabricated by tube furnace diffusion using a POCl 3 source, is widely used as a dopant source in the manufacturing of crystalline silicon solar cells.