Musical chairs proceeds apace in the DRAM industry as Elpida and Qimonda sign up to an alliance, as ProMos looks for a technology partner (expected to be either Hynix or Elpida), and as Micron and Nanya agree to exchange technology and set up the manufacturing joint venture MeiYa.

Qimonda and Elpida will collaborate on 40nm products, using Qimonda's buried word line technology and Elpida's stacked capacitor technology, scheduled for manufacturing in 2010. They will exchange engineers between Hiroshima and Dresden and will prepare for a manufacturing joint venture.

ProMOS, which started off as a joint venture between Qimonda's parent Siemens Semiconductor and Mosel-Vitelic of Taiwan, is said to be talking to Elpida, with ProMos boss Ben Tseng conceding that ProMos is looking for a next-generation technology partner. However Hynix could also be in the running to be ProMos' technology partner.

MeiYa Technology, the 50/50 joint venture between Micron and Nanya, is both a technology partnership and a manufacturing joint venture. The technology exchange kicks in at the sub-50nm generation, and the manufacturing will take place in an old 200mm fab being upgraded to 300mm to run wafers in 2009.

The Nanya-Micron deal essentially ends the Qimonda-Nanya relationship which produced the Qimonda-Nanya joint venture Inotera Memories.