BS IEC 62951-2-2019 pdf download.Semiconductor devices – Flexible and stretchable semiconductor devices Part 4: Fatigue evaluation for flexible conductive thin film on the substrate for flexible semiconductor devices.
This part of IEC 62951 specifies an evaluation method of the bending fatigue properties of conductive thin film and flexible substrate for the application at flexible semiconductor devices.
The films include any films deposited or bonded onto a non-conductive flexible substrate such as thin metal film, transparent conducting electrode, and thin silicon film used for flexible semiconductor devices. The electrical and mechanical behaviours of films on the substrate are evaluated. The fatigue test methods include dynamic bending fatigue test and static bending fatigue test.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 62047-2:2006，Semiconductor devices – Micro-electromechanical devices – Part 2:Tensile testing method of thin film materials
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the followingaddresses:
●IEC Electropedia: available at ht://ww.electropedia.org/
●Iso Online browsing platform: available at htp://ww.iso.org/obp
3.1 radius of arc corresponding to the curvature of the central line between innermost and outermost surfaces of flexible electronic devices during a bending test
[SOURCE: IEC 62715-1-1:2013, 2.5.1, modified – The words “a flexible display device” have
been replaced by “flexible electronic devices”.]
critical bending radius bending radius at which the failure of the flexible semiconductor devices occurs
Note 1 to entry: For the conductive films, the electrical resistance starts to exceed a predefined limit, and/orfracture of the film or caused by delamination or initiation of the cracks occurs, or by damage of the substrate.
flexible substrate
substrate with flexibility onto which conductive thin films will be deposited, bonded or attached
[SOURCE: IEC 62951-1:2017, 3.1.4.]
3.4 outer bending test
test, where the test piece is bent into a convex shape (n)
Note 1 to entry: Outer bending test induces tensile stress on the flm.
Note2 to entry: There are different names of outer bending test such as outward, face-out, or convex bending test.
3.5 inner bending test
test, where the test piece is bent into a concave shape (心)
Note 1 to entry: Inner bending test induces compressive stress on the film.
Note 2 to entry: There are different names of inner bending test such as inward, face-in, or concave bending test.
3.6 dynamic bending fatigue test
test designed for determining the bending properties of flexible semiconductor device to withstand the repeated strain for a certain period of time
3.7 static bending fatigue test
test designed for determining the bending properties of flexible semiconductor device to withstand the same strain for a certain period of time
Note 1 to entry: Test piece is bent at fixed bending radius for any length of time.
3.8 S-N curve
plot of stress (S) against the number of cycles to failure
[SOURCE: IEC 62047-12:2011, 3.3, modified – The expression “plot of stress or strain” has been replaced by “plot of stress”.]
3.9 8-N curve
plot of strain (&) against the number of cycles to failure
[SOURCE: IEC 62047-12:2011，3.3， modified – The term has been modified and the expression “plot of stress or strain (S)” has been replaced by “plot of strain (a).]BS IEC 62951-2 pdf download.