摘要:
A test structure (200, 200′) having an array (224) of test devices (220) for detecting and studying defects that can occur in an integrated circuit device, e.g., a transistor (144), due to the relative positioning of one component (100) of the device with respect to another component (108) of the device. The test devices in the array are of a like kind, but vary in their configuration. The differences in the configurations are predetermined and selected with the intent of forcing defects to occur within at least some of the test devices. During testing, the responses of the test devices are sensed so as to determine whether or not a defect has occurred in any one or more of the test devices. If a defective test device is detected, the corresponding wafer (204) may be subjected to physical failure analysis for yield learning.
摘要:
In random defect yield simulation, a specific defect size interacts with a specific physical design and has a calculated probability of failure associated with it. The failure model is in terms of probability of failure. It provides a solution to the random defect yield simulation problem of chips with a built-in redundancy scheme. The solution first defines the independent failure modes of the chip with a built-in redundancy scheme and efficiently models each mode. Then, it may accumulate the respective probability of failures according to the chip's architecture.
摘要:
Disclosed is a flexible command multiplication scheme for the built-in-self test (BIST) of a high-speed embedded memory array that segments BIST functionality into remote lower-speed executable instructions and local higher-speed executable instructions. A stand-alone BIST logic controller operates at a lower frequency and communicates with a command multiplier using a low-speed BIST instruction seed set. The command multiplier uses offset or directive registers to drive a logic unit or ALU to generate “n” sets of CAD information which are then time-multiplexed to the embedded memory at a speed “n” times faster than the BIST operating speed.