In spite of the fact that Taiwan Semiconductor Manufacturing Company initiated mass production using 40nm process technology nearly a year ago and other companies have been attempting to start volume production at 40nm node for about half a year, the percentage of fully-functional chips made using 40nm fabrication process is still below 70%.

Foundry chipmakers, including Taiwan Semiconductor Manufacturing Company (TSMC), have been struggling to increase their yields on 40nm to over 70%, reports DigiTimes web-sites citing industry sources. Back in November ’09 TSMC said officially that the 40nm chip yield was approximately 60%, which means that it has increased slightly so far. However, earlier it was indicated that yields were down to 40% in October.

TSMC said last year that 40nm chips would account to 10% of the company’s revenue in Q4 2009.

At present only ATI, graphics business unit of Advanced Micro Devices, Altera and Nvidia Corp. use TSMC 40nm process technology, as a result, only their products are affected by the low yields. But while ATI has so far supplied over two million of various 40nm chips, including those that support DirectX 11, Nvidia Corp. is only shipping small low-end 40nm chips and has to delay its highly-anticipated code-named GF100 (aka NV60, G300, GT300) graphics processor.

Since United Microelectronics Corp. (UMC) only has one customer for 40nm node, it should be kept in mind that TSMC still produces the lion's share of 40nm chips in Taiwan.

Tags: TSMC, 40nm, ATI, AMD, Altera, Nvidia, Semiconductor, Evergreen, Fermi, GF100, NV60, GT300, Geforce, Radeon