MBIST Engineer

Project

Work done for a product or program.

• Insert and configure MBIST controllers, comparators and collars across hundreds of embedded memory instances using Tessent MemoryBIST or SMS (Synopsys STAR Memory System).
• Implement built-in redundancy analysis and soft/hard repair flows including fuse box integration, eFuse programming and repair-signature retargeting.
• Integrate MBIST access into the IJTAG/IEEE 1687 network so memories can be tested at wafer sort, at final test and at power-on boot in the field.
• Verify MBIST operation through RTL and gate-level simulation with fault injection to prove the controller actually detects the modelled defects.
• Close MBIST timing with the physical design team, including at-speed memory clocking, pipeline stages and comparator paths.
• Support memory characterisation by implementing programmable margin modes such as VMIN search, timing knob sweeps and data retention testing.
• Diagnose failing memories in silicon using MBIST failure bitmaps and hand off bitmap data to failure analysis and the memory IP vendor.
• Maintain the memory test collateral database mapping every instance to its controller, algorithm set, repair resources and coverage.
• Support boot-time and periodic in-field MBIST scheduling for automotive and safety-critical parts.

Function

Work that keeps the discipline running: methods, tools, suppliers and people.

• Select and tune memory test algorithms — March C-, March SS, checkerboard, butterfly, retention and data-bit pattern tests — against the memory vendor's defect models.

Project

1. Produce and hand over the role's key deliverables
   • MBIST-integrated RTL/netlist with controllers and repair logic
   • Memory test algorithm specification per memory type
   • Repair and fuse map documentation with signature format
   • MBIST simulation and fault injection verification report
   • Memory failure bitmap extraction flow and diagnostic collateral
   • Memory instance-to-controller coverage matrix
2. Develop the test solutionGeneral
   • Define the test plan and coverage targets
   • Write and debug the test program
   • Design or specify the test hardware
3. Release to productionGeneral
   • Correlate results across testers and sites
   • Optimise test time
   • Release the program under change control

Function

1. Maintain test infrastructureGeneral
   • Keep program libraries and standards current
   • Plan tester and hardware capacity
2. Improve methodsGeneral
   • Review escapes and adjust coverage
   • Develop data analysis tools