Reliability
Continuous production of durable products under defined conditions requires modern qualification and monitoring procedures for technology development as well as for any changes.
Melexis uses state-of-the-art test equipment to perform reliability investigations.
To fulfil the high requirements for a flexible controlled production Mlexis uses a modular qualification strategy including sophisticated reliability test methods on wafer level.
Modular Quality Strategy
The qualification procedures will be realized in according to international recognized standards or guidelines such as AEC-Q100; MIL 883; CECC 90 000; IEC 68; JEDEC, etc.
Conformity tests (monitoring) are carried out in determined intervals for all qualified technologies and package families.
For the qualified technologies and products we fulfil the high reliability requirements of our customers. The long term reliability (long term failure rate ) is calculated on 150 degrees C / 125 degrees C test temperature (Tj </=175 degrees C) and is expressed in Fit.
(Fit = Failure in time = 10-9 per hour; e.g. 1 Fit means 1 Failure on 109 device hours)
Melexis shows evidence of a competitive long term reliability (fit rate). The requirements for high outgoing quality and reliability of each delivery lot are realized by an integrated comprehensive process- monitoring.
Additionally WLR (Wafer- Level Reliability) tests are performed for fast reliability evaluation at test structures. This offers highest possible reliability of sensitive technology parts.
WLR - (Wafer Level Reliability) tests are used in different stages of development and production:
Use in |
Applied tests |
Target / Result |
Technology -
Development
|
- WLR support for engineering lots
(special tests) |
- Definition of Save Operation areas
- Evaluation of process homogenity (lot/ lot/ wafer-wafer / wafermap)
|
Technology -
Qualification |
|
- Verification of Save Operation areas
- Verification of process homogenity (lot/ lot/ wafer-wafer / wafermap)
|
Process in production |
- WLR Monitoring lot by lot using WLR fast / super fast tests
|
- Verification of process homogenity over long time
- Identification of spontaneous
(IN-LINE: Short loop feedback)(END-OF-LINE: integral process evaluation)
- Identification of spontaneous process deviations and feedback
- Identification of slow process drifts and feedback
|
|
|
- Verification of process homogenity over long time
- Using test methods of well understood physics/ correlation
|
Various test methods for investigation and assessment of oxide integrity, metallization as well as transistor stability (hot carrier) are used.
|