Mechanisms for built-in self test and repair for memory devices
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsSaman Adham, Chao-Jung Hung
Life of this patent
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Abstract
This description relates to a system for storing repair data of a random access memory (RAM) array in a one-time programming memory (OTPM). The system includes the RAM array, wherein the RAM array includes a main memory, redundant rows and columns, and a first repair register memory. The system further includes a built-in self-test-and-repair (BISTR) module having a second repair register memory, wherein the BISTR module is used to test and repair the RAM array. The system further includes the one-time programming memory (OTPM) for storing repair data from more than one test and repair stages for the RAM array, wherein the repair data from different test and repair stages are stored in a same data segment.
Claims20
A method of storing repair data of a random access memory (RAM) array in a one-time programming memory (OTPM), comprising:
- performing a first test and repair of the RAM array using a built-in self-test-and-repair (BISTR) module to determine first repair data for the RAM array, wherein the RAM array has redundant rows and columns for repair;
- storing the first repair data of the RAM in the OTPM;
- loading the first repair data in a repair memory of the RAM array;
- loading the first repair data in a repair memory and in a duplicated repair memory of the BISTR module;
- performing a second test and repair of the RAM array to determine second repair data of failed bits not included in the first repair data;
- storing the second repair data in the repair memory of the BISTR module and in the repair memory of the RAM array;
- processing the repair data in the repair memory and the duplicated repair memory of the BISTR module using an XOR gate;
- storing the output of the XOR gate in the repair memory of the RAM array;
- and
- storing content of the repair memory in the OTPM.
The method of method 1, wherein the first repair data and the second repair data are stored in a same segment and are next to one another in the OTPM.
A system for storing repair data of a random access memory (RAM) array in a one-time programming memory (OTPM), comprising:
- the RAM array, wherein the RAM array includes a main memory, redundant rows and columns, and a first repair register memory;
- a built-in self-test-and-repair (BISTR) module having a second repair register memory, wherein the BISTR module is used to test and repair the RAM array;
- and
- the one-time programming memory (OTPM) for storing repair data from more than one test and repair stages for the RAM array, wherein the repair data from different test and repair stages are stored in a same data segment.
A system for storing repair data of a random access memory (RAM) array in a one-time programming memory (OTPM), comprising:
- the RAM array, wherein the RAM array includes a main memory, redundant rows and columns, and a first repair register memory;
- a built-in self-test-and-repair (BISTR) module having a second repair register memory, wherein the BISTR module is used to test and repair the RAM array, and wherein the second repair memory includes a repair register segment and a duplicated repair register segment;
- and wherein the BISTR module has a XOR gate having one input from the repair register segment and another input from the duplicated repair register segment;
- and
- the one-time programming memory (OTPM) configured for storing repair data from more than one test and repair stages for the RAM array, wherein the repair data from different test and repair stages are stored in a same data segment.
Dependencies are inferred from the claim text.