Abstract
Degradation is seemingly fundamental to all things in nature. Often this is described as one of the consequences of the Second Law of Thermodynamics—entropy (disorder) of isolated systems will tend to increase with time. The evidence for degradation is apparently everywhere in nature. A fresh coating of paint on a house will eventually crack and peel. The finish on a new automobile will oxidize with time. The tight tolerances associated with finely meshed gears will deteriorate with time. The critical parameters associated with precision semiconductor devices (threshold voltages, drive currents, interconnect resistances, capacitor leakage, etc.) will degrade with time. In order to understand the useful lifetime of the device, it is important to be able to model how critically important materials/device-parameters degrade with time.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
S, as used in this chapter, is a material/device parameter and should not be confused with S used for entropy in Chap. 2.
- 2.
Note that Ao is positive and must have the units of reciprocal-time to the mth power.
- 3.
- 4.
The term device is very general: any apparatus that serves some useful purpose.
- 5.
If significant degradation (but not failure) started in the warrantee period, does one have a claim? Sometimes, it can be very important to be able to identify the onset of degradation.
- 6.
Note that even though the degradation started at 10.5Â months, the degradation at 12Â months is so small that it went undetected by the measuring instrument.
- 7.
An example of competing mechanism comes from the joining/bonding of dissimilar materials. During the bonding of dissimilar metals at high temperatures, inter-diffusion of the two materials is usually required in order to establish good bonding. Initially, this inter-diffusion of materials will cause an increase in bonding strength. However, often during the later stages of inter-diffusion, the bond strength can start to weaken due to Kirkendall voiding.
Author information
Authors and Affiliations
Rights and permissions
Copyright information
© 2019 Springer Nature Switzerland AG
About this chapter
Cite this chapter
McPherson, J.W. (2019). Time-Dependence of Materials and Device Degradation. In: Reliability Physics and Engineering. Springer, Cham. https://doi.org/10.1007/978-3-319-93683-3_3
Download citation
DOI: https://doi.org/10.1007/978-3-319-93683-3_3
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-93682-6
Online ISBN: 978-3-319-93683-3
eBook Packages: EngineeringEngineering (R0)