Infineon has a section on their website for Package/Case documentation. Some of the documents available are:
Package Outline, Package Part Marking, REACH Compliance, Rohs Compliance, and Package Tape & Reel Specifications
Inside the RoHS Compliance document will include the Composition, Solder Reflow Profile, and Tin Whisker Report
The link will involve some navigating. You will need to know the type of part, and then the package/case of the part you would like the documents for.
Here is the link: