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AN 113: Plastic Package Reliability & Testing
®

Altera Corporation
1

Plastic Package
Reliability & Testing

June 1999, ver. 1
Application Note 113

A-AN-113-01

Introduction

Designers expect Altera

®

devices to perform in a variety of environments
and conditions. Reliable devices decrease design and maintenance costs
and increase product life cycles. Altera submits its devices to a series of
strenuous tests to ensure that they provide maximum value to end users.
Device reliability is generally defined as the probability that a device will
perform its intended function under specified operating conditions
throughout its life. As a result, industry-wide reliability guidelines were
established.
Altera devices exceed the reliability requirements established by the
Electronic Industries Association (EIA) and Joint Electron Device
Engineering Council (JEDEC). JEDEC qualification tests ensure that
Altera devices meet or exceed these reliability standards. Tests are
performed under extreme conditions and the failure rate can be
extrapolated to typical conditions using equations that describe the
acceleration of failure mechanisms. This application note describes some
of the tests used for device reliability testing, including:

s

Stress-test-driven qualifications

s

Moisture/reflow sensitivity

s

Temperature cycling

s

Humidity bias testing

s

HAST testing

s

Autoclave testing

f

For more information on Altera device reliability, see the

Altera Device
Reliability Report

, which is available from Altera literature services.

EIA/JEDEC
Standards

EIA/JEDEC standards identify testing requirements that range from
general to specific. For example, all plastic package testing must follow
general guidelines specified by JESD 47, but only certain types of device
packages may be required to undergo HAST testing. The pyramid in
Figure 1
illustrates the hierarchy for EIA/JEDEC testing procedures and
serves as the model for Altera testing requirements.

2
Altera Corporation
AN 113: Plastic Package Reliability & Testing

Figure 1. EIA/JEDEC Testing Hierarchy

As new technologies are developed, Altera engineers rely on the
EIA/JEDEC testing hierarchy to qualify new semiconductor
architectures. New architectures may include smaller process geometries,
an increased number of die layers, increased gate and I/O pin counts,
decreased voltage levels, and changes in package material composition.
These design changes affect the reliability of a device. As a result, the
device may require a different set of tests as technologies advance.
The Stress-Test-Driven Qualification of Integrated Circuits (JEDEC
Std. 47) guideline determines which tests a new design must undergo and
helps product engineers identify and correct flaws that may arise. The
guideline also identifies sample size requirements and testing
qualifications for new devices to help expose process flaws.

f

For more information on EIA/JEDEC standards, visit the JEDEC web site
at

http://www.jedec.org

.

Moisture/
Reow
Sensitivity

Altera uses moisture/reflow sensitivity testing (J-STD-020A) guidelines
to inform customers of device sensitivity to moisture-induced stress. After
testing, devices are assigned sensitivity levels. These classification levels
are useful in determining the proper storage and handling of Altera
devices to prevent thermal and mechanical damage during solder reflow
or repair. Moisture sensitivity levels determine the length of time a device
can be exposed to humidity. See
Table 1
.
JESD 47
Stress-Test-Driven
Qualification
of Integrated Circuits
J-STD-020A
Moisture/Reflow Sensitivity
Classification for Non-Hermetic
Solid State Surface Mount Devices
JESD22-A110-A
HAST Testing
JESD22-A104-A
Temperature
Cycling
JESD22-A102-B
Accelerated Moisture
Resistance
Unbiased Autoclave
JESD22A-101-B
Steady State
Temperature
Humidity Bias
Life Test
General
Guidelines
Specific Testing
Requirements

Altera Corporation
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AN 113: Plastic Package Reliability & Testing

Note:

(1)
Condition percentages denote relative humidity levels.

The device classification applies to all surface mount packages: ball-grid
array (BGA), small-outline integrated circuit (SOIC), plastic J-lead chip
carrier (PLCC), plastic thin quad flat pack (TQFP), plastic quad flat pack
(PQFP), and power quad flat pack (RQFP) device packages. Because of
their composition, these device packages could be damaged during solder
reflow.
The vapor pressure of moisture trapped inside of a plastic package
increases when the package is exposed to high solder reflow
temperatures. This pressure can lead to internal delamination, internal
cracks, bond damage, wire necking, bond lifting, die lifting, thin film
cracking, or cratering beneath the bonds. In extreme cases, the package
emits an audible crack, also known as the popcorn effect.
To minimize the chances of device damage, Altera recommends using a
100

%

convection reflow system that is capable of maintaining the reflow
profiles required by the J-STD-020A standard.

f

For more information on reflow soldering, see

Application Note 81 (Reflow
Soldering Guidelines for Surface-Mount Devices

)
.
Small, thin devices can reach body temperatures greater than 220 C when
reflow-soldered to boards profiled for larger devices. To compensate for
this difference, some small packages have been reclassified to withstand
235 C.
Table 2
defines the transition thickness/volume of packages that
can reach 235 C when reflow soldered to boards with larger devices.

Table 1. Moisture Sensitivity Levels

Level
Floor Life
Soaking Requirements
Time
Conditions

(1)

Time (Hours)
Conditions

(1)

1
Unlimited

30 C/85

%


168
85 C/85

%

2
1 Year

30 C/60

%


168
85 C/60

%

2a
4 Weeks

30 C/60

%


672
30 C/60

%

3
168 Hours

30 C/60

%


192
30 C/60

%

4
72 Hours

30 C/60

%


96
30 C/60

%

5
48 Hours

30 C/60

%


72
30 C/60

%

5a
24 Hours

30 C/60

%


48
30 C/60

%

6
Time On Label

30 C/60

%


Time On Label
30 C/60

%

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Altera Corporation
AN 113: Plastic Package Reliability & Testing

Note:

(1)
VPR phase will not exceed 219

C.

For more information on moisture/reflow sensitivity classification for
plastic packages, refer to

JEDEC Standard J-STD-020A

.
Package reliability can also be affected by the rate at which a particular
device reaches its testing temperature.
Table 3
lists classification reflow
profiles for two types of reflow convection methods: full convection and
infra-red convection.

Note:

(1)
Altera recommends using the full convection method for production.
(2)
See
Table 2
.

Temperature
Cycling

Temperature cycling (JESD22-A104-A) is performed to determine the
resistance of Altera devices to high and low temperature extremes. This
environmental stress test is designed to simulate the extensive changes in
temperature to which devices and packages may be exposed. To pass the
test, devices must not show signs of damage such as cracking, chipping,
or breaking.
Table 4
shows the classifications for Altera devices.

Table 2. Small Device Reflow Conditions

Conditions
Package Thickness

2.5 mm & All
BGA Packages
Package Thickness
< 2.5 mm & Package
Volume

350 mm

3

Package Thickness
< 2.5 mm & Package
Volume < 350 mm

3

Convection Temp.
220 +5/-0 C
Convection 220 +5/-0 C
Convection 235 +5/-0 C
VPR Peak Temp.
215-219 C
215-219 C
N.A.

(1)

IR/Convection Temp.
220 +5/-0 C
220 +5/-0 C
235 +5/-0 C
Package Type
All BGA, FineLine BGA
packages
All other packages
T44, Q44, T100, T32
packages

Table 3. Classification Reflow Profiles

Condition
Full or Infra-Red Convection

(1)

Average ramp-up rate (183 C to peak)
1 - 3 C/second
Preheat temperature 125 C (

±

25 C)
120 seconds maximum
Temperature maintained above 183 C
60 to 150 seconds
Time within 5 C of actual peak
temperature
10 to 20 seconds
Peak temperature range

(2)

Ramp-down rate
6 C/second maximum
Time 25 C to peak temperature
6 minutes maximum

Altera Corporation
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AN 113: Plastic Package Reliability & Testing

Temperature cycling may also expose weaknesses in packages that are
composed of different materials. If device packages are composed of
different materials, expansion and contraction of the package materials
can occur at different rates when exposed to temperature extremes.
Figure 2
shows an example of the differences in the thermal coefficients of
expansion between two materials with identical lengths.

Figure 2. The Effects of Thermal Coefcient of Expansion on Two Materials

Because the materials are in contact with each other, the actual expansion
of the two materials is a composite of the two. Both materials expand to
the same length when placed together, which places extra stress on
material 1. The materials act similarly during compression. As a result,
shear stresses can occur at the joint between the two materials, which
results in the passivation of metal layers.

Table 4. Temperature Cycling Classifications

Classification
Low Temperature (C)
High Temperature (C)

A
55 (+0, 10)
+85 (+0, 10)
B
55 (+0, 10)
+125 (+0, 10)
C
65 (+0, 10)
+150 (+0, 10)
D
65 (+0, 10)
+200 (+0, 10)
F
65 (+0, 10)
+175 (+0, 10)
G
40 (+0, 10)
+125 (+0, 10)
H
55 (+0, 10)
+15