The stay in place method that we use is listed here:
We the StencilQuik product for BGAs. Pretty easy to use. Put the stencil down (eyeballs for 1.0mm and greater), "smear" paste flux on bottom of balls, fit the balls into the apertures, put into toaster oven and off you go!
How are you attaching area array devices to prototype boards?
The methods I have seen the most common for protos are: 1. Outsource it! 2. Print solder paste with a stencil and hand place 3. Use a stay-in-place stencil whihc allows the user to "fit it in to" the apertures and handplace -probably only good to 0.8mm pitch with some type of magnification for placement of the stencil).
