Solar Cell Encapsulation

Our first solar cell encapsulation experience!
Third try - Second try - First try

Behind the scenes:
Tedlar backsheet - EVA film - 1/3 solar cell - EVA film - Teflon FEP film

Covered with a couple layers of breathers and vacuum bagging film, and sealed, they're all set to be baked under air tight condition!

Temperature: 180°F, Pressure: 14psi, Countdown: 30 minutes

We failed on our first try :( 
Reason of failure is shown in the picture below.

Second try: We shifted the thru-bag vacuum connector so that it doesn't sit on top of the solar cell...and we baked them for 45 minutes..but we failed again! 
We found out that the temperature range of the top film is up to 205°F, but due to the temperature fluctuation of the toaster oven, the temperature sometimes exceeds 205°F. We suspected that this caused the formation of the dimples. (Sorry if this picture ruined your appetite) 

Third try: 
Temperature: 175°F, bake time: 30 minutes, cool down: 21 minutes.
This time the temperature never exceeded 205°F and we succeeded!!!
No bubbles, dimples almost nonexistent.

In the near future we will encapsulate the entire cell instead of just one third the cell. We will also sandwich them with two aluminium plates.