The rigamarole of Cree's Wolfspeed sale has flown under the radar for months. Last year, Infineon said that it would pay $850 million for the business, which would expand its portfolio of chips for power management and wireless equipment. But that is a drop of the chip industry's billions of dollars in consolidation.

But the story changed last month when the United States security panel that approves such deals withheld its blessing. One possibility is that regulators were worried about losing Wolfspeed's gallium nitride expertise. The ruling set off hand-wringing at both companies involved in the deal, which quickly fell apart. 

When layered on other semiconductors, gallium nitride can handle higher voltages and higher temperatures than normal silicon. It has gradually spread into everything from antiballistic missile radar to cellular equipment. Wolfspeed also fills custom chip orders for the Department of Defense and contractors like Lockheed Martin.

In recent years, the regulators have rejected several deals that would have allowed Chinese chipmakers to gain insight into manufacturing GaN chips. But the failure of the latest deal hints at how worried the United States is of losing its edge in semiconductors. Infineon is based in Germany, a traditional ally.

After the announcement, Electronic Design covered the deal sparingly. But its sister publication, Microwaves & RF has followed every step of the closing process. Here is all the reporting that the magazine has done on the deal:

September 2015: Cree Renames Power and RF Division, Emphasizing Wide Bandgap Devices

November 2015: Inside Track with John Palmour, Co-Founder and CTO, Wolfspeed

July 2016: Infineon Buys Cree's Wolfspeed to Expand Power and Wireless Chips

November 2016: Infineon Cuts through Choppy Regulatory Waters, Though Major Review of Wolfspeed Deal Lies Ahead

February 14, 2017: With Regulators Concerned, Infineon's Deal for Wolfspeed is in Jeopardy

February 17, 2017: Infineon's Deal for Wolfspeed Falls Apart, Showing Delicacy of Gallium Nitride

February 23, 2017: Winding Down the Wolfspeed Saga, an Executive Leaves and an Experiment Ends