Reliability

Is there lifetime of the semiconductor?

The life of a semiconductor device is determined by the durability of the wiring of the constituent elements of the device, the oxide film, and the transistors.
The durability of a semiconductor device is assured by reliability design (Note).
Standard products are designed to have a useful life of at least 10 years if used under the recommended operating conditions, and sometimes they may last for as long as several tens of years.
The term "life" as used here refers to the life of individual product itself.

Reference document:
Review of Quality and Reliability Handbook
(Note) Chapter 1, 1.3.2 (2)

Why is the life design 10 years?

Upon request from customers, we design devices to ensure a wear-out failure stage that extends to 10 years.



Related FAQ:
Bathtub curve

(2006/12)

What is the reliability of a semiconductor device?

JIS defines reliability as follows.

"Characteristics that enable an item to perform its required functions under the stipulated conditions and for the stipulated time period"
(Japan Industrial Standard Z 8115 "Reliability Terms")

To put it simply, it means the "characteristics that enable a product to function without faults for a specific usage period" and refers to the time-related quality of the product.
Parameters used for the quantitative measurement of reliability, include reliability level, failure rate, and mean time to failure.

Reference document:
Review of Quality and Reliability Handbook Chapter 2

Is the life of semiconductor devices affected by temperature?

Yes. Temperature and degradation of electrical characteristics are closely related.
Generally, degradation accelerates as the temperature rises.
A semiconductor device rapidly degrades at temperatures that exceed the maximum rated temperature.
Care must be exercised when using devices at high temperatures.

Reference document:
Review of Quality and Reliability Handbook

I have a product whose production was stopped several years ago.
It has been left at room temperature for several years.
Is there any difference between using a product immediately after production and after storing it for several years?

Power supply makes a product progresses The degradation.
If the product is a plastic package product and has never been mounted, bake it in order to dehydrate it before using it.
Also check that the leads are not rusty and check the solder wettability.
Generally, the guaranteed storage period of a product is 2 years after shipment.

Reference document:
Review of Quality and Reliability Handbook

Does an X-ray fluoroscopic examination have any effect on the life of a semiconductor?

A normal X-ray fluoroscopic examination should have no effect on an NEC Electronics semiconductor.
As is described in the Review of Quality and Reliability Handbook, an X-ray fluoroscopic examination is used as a non-stress screening method, and is also used for failure analysis.

(2006/04)

Is the failure rate of each product listed somewhere?

Since the failure rate varies depending on the temperature, power supply voltage, and other conditions, the failure rate (fit) for each product is not listed. To calculate the failure rate of a given product, refer to Chapter 2 and Chapter 5 of the Semiconductor Failure Rates information document. Chapter 2 explains the failure rate calculation procedure, and Chapter 5 lists the basic failure rates (λb) and the activation energy (Ea) of individual products.
For products that are not listed in this document, request the needed parameters through the seller of that product.

(2006/12)

How does a semiconductor product operate if its internal circuit is damaged?

The operation cannot be specified.
There are three damage failure modes, short, open, and ohmic (resistivity).
Which mode will take place cannot be predicted.
These failure modes and influences on the other internal circuits cannot be specified.

What is the value LnH(t)?

LnH(t) is a parameter for estimating the hazard probability of the Weibull distribution.
Ln is a natural logarithm and H(t) indicates the Weibull distribution.
For details, refer to "Appendix B.4 Estimation of Reliability Analysis Using Probability Paper (Weibull Hazard Probability Paper)" in the Review of Quality and Reliability Handbook. For details on the Weibull distribution, refer to "Using Weibull Probability" published by the Japanese Standards Association.

Regarding the ESD (Electrostatic Discharge) test to confirm electrostatic tolerance, is it true that applying such high voltage for such a short time does not cause any problems?

No. Actually, the ESD test is used just to confirm the amount of damage done to pins during this brief period, and reliability cannot be guaranteed for product units that have undergone this test. Even if pin damage does not seem to occur during this test, abnormal operations may occur in the short term.
Do not apply voltage that exceeds the maximum rating to any mass produced products.

(2008/04)

I received your products uncoated with bare metal of the pin section close to the package body. Are they defective?

Depending on the package, some products may be processed like this, so it is not a defect.
For discrete and linear IC products housed in a through-hole type package (products that are dipped rather than coated), as long as the pins are covered as far as the stopper section (the boundary between the thin and thick parts), the product is OK.
Also, in some 3-pin minimold packages (SC-59) that have a slightly broad area near the base of the lead, this area may not be coated. The 2SA812A is one such example (the 2SA812, however, is fully coated).

(2008/01)

Are the semiconductor products of NEC Electronics designed to withstand radiation?

No, generally they are not designed to withstand radiation. The sets in which they are to be used should be designed to withstand radiation exposure.
For further information, see "Cautions on use environment" in the Review of Quality and Reliability Handbook "Use of Semiconductor Devices".

(2008/02)

Are the reliability and characteristics of semiconductor devices affected at altitudes exceeding of 2,000 m?

No, they are not affected as long as their storage temperature and operating temperature are observed.
Barometric pressure at an altitude of several 1,000 m does not pose any problem to the semiconductor devices. It can be said that cameras, radio equipment, and vehicles have been used at these high altitudes without problem, and no malfunctioning has been reported in relation to devices used in aircrafts.

(2008/02)

Is there any other available information in addition to this FAQ?

Refer to "Appendix D Q&A" in the Review of Quality and Reliability Handbook.