Photovoltaic devices with silicon dioxide encapsulation layer and method to make same

An architectural photovoltaic window, comprising:

• a first protective window layer;
• first transparent electrical contacts formed on the first protective window layer;
• a P-N junction formed between doped semiconductor materials on the first protective window layer and the first transparent electrical contacts, wherein the P-N junction is adapted to produce photovoltaic current in response to radiant energy reaching the P-N junction;
• second transparent electrical contacts formed on one or more of the doped semiconductor materials;
• and
• a second protective window layer of 250 microns thickness or more formed of amorphous silica on one or more of the doped semiconductor materials and the second transparent electrical contacts, using a liquid aerosol spray of one or more metalorganic precursors at formation temperatures less than 600° C., wherein the second protective window layer is adapted to allow radiant energy to pass therethrough en route to the P-N junction, the second protective window layer including a high optical transparency layer of amorphous silica, having a silicon dioxide chemistry greater than 75 molar percent.