For those of us in the heat sink, heat sink attach and thermal design space heat sink attach is a big bugaboo. There are many options to choose from for sure and each has it’s own pluses and minuses.  The key is to choose the right attachment method given the thermal requirements, application and cost. Many times engineers will just default to tape and when in doubt will choose epoxy.  At ATS we’ve seen the use of thermal epoxy so much it makes us weep!  Epoxy seems like the answer to make sure a heat sink stays on during shock and vibe testing. The use of the epoxy is subject to many variables. There are other options, two of which just came onto the market.
Alpha Novatek has just released it’s Quick Set family of Heat Sinks. Here’s a description from their press release
Electronic components have become faster and more compact, generating more heat and increasing thermal densities. This has led to the use of heat sinks of increased size and mass. One of the biggest challenges for thermal/mechanical engineers is mechanically mounting larger heat sinks while minimizing the amount board real estate used by the attachment mechanism. Generating sufficient attachment force is also critical with regards to mechanical security and proper performance of thermal interface materials.
Alpha’s new Quick Set series heat sinks have been designed to address both issues, providing secure and reliable attachment while requiring the absolute minimum of board real estate.
In a nutshell, Quick Set requires a small mounting pins be placed onto a PCB. Mounting pins only require 1.8mm[.071″] diameter holes in the PCB. Then a heat sink can be clipped on creating a secure attachment that uses minimum space.  It also appears it can handle oversize heat sinks too, a real boon with large footprint semiconductors. More information and photos are on the official announcement on Alpha Novatech’s web site at this link here.
For ATS’s part, we’ve approached this same problem of heat sink attachment by way of clip technology.  Our latest is superGRIP, an attach technology which puts a clip around the semiconductor and allows spring to hold the heat sink down. Our studies and those of our major customers indicate superGRIP does not put strain on a BGA.  superGRIP’s differentiator over Alpha’s Quick Set is that superGRIP does not require any holes in an electronics board PCB.  It also provides the precise pressure to allow phase change interface material to be used to it’s best advantage with a heat sink. You can learn more about superGRIP by visiting ATS’s Slideshare Channel or by visiting ATS superGRIP Web Site.