Analysis of retention tail distribution induced by scaled shallow trench isolation for high density DRAMs

The transistor hump induced by shallow trench isolation (STI) was quantitat ively analyzed at the test site of DRAM product wafers, and it was directly correlated to the retention fail-bit distribution of the DRAMs. It was fou nd that the hump magnitude tracks quite well the tail distribution of reten tion time failure, thus establishing a direct link between the hump magnitu de estimated from the test transistors and the retention time distribution of the product. (C) 2001 Elsevier Science Ltd. All rights reserved.