MIL- STD-883F 2004 TEST METHOD STANDARD MICROCIRCUITS.pdf - 第350页

MIL-STD-883F METHOD 2018.4 18 June 2004 38 APPENDIX A 40.3 .1 Reliab ility evalu ating . The manufac turer must have i n place a s ystem f or evaluati ng the rel iabil ity of t he metal syst em. The sys tem shal l enable…

MIL-STD-883F

METHOD 2018.4

18 June 2004

APPENDIX A

40. REQUIREMENTS

40.1 Design controls

. Design includes device design and process development. Device design includes all steps and

supporting systems needed to translate a functional description for a device into a pattern generating data base. Process

development includes selection of materials, tooling, and process conditions that may significantly affect metal integrity. The

design process is a major consideration in establishing metal integrity.

40.1.1 A manufacturer's design system must include controlled, documented rules based on the manufacturer's

processing capabilities. These rules shall specify feature size and spacing requirements, taking into account size changes

that occur during processing. Manufacturers shall be able to justify their rules based on expected process variations. In

addition, documented reliability rules shall exist which establish the electrical characteristics for each technology, taking into

account processing materials, tolerances and limitations. The manufacturer shall have a system for checking designs for

rule violations, and a system for correcting violations. Design rules shall consider the maximum current density (calculated

as described in appendix A of MIL-PRF-38535) which shall be determined using worst case operating conditions and taking

into consideration current crowding at contacts and vias. The manufacturer shall ensure that worst case processing

conditions (such as alignment, metal thickness, line width, and contact/via size) do not result in violation of current density.

Current density for a technology shall be at a level such that there is sufficient margin to ensure that failure will not result

from electromigration in the specified lifetime of the device.

40.1.2 Process development

. The manufacturer's design must take into consideration known levels of defects in the

process. The process developed by the manufacturer must produce metallization that has the electrical and mechanical

properties consistent with the design rules of 40.1.1, and reliability goals for the technology. Mechanical stress in the metal

after final processing shall be understood. The manufacturer shall demonstrate, with results from appropriate designed

experiments, that the desired electrical and mechanical properties have been achieved, and that the interaction of other

process parameters on metal integrity parameters (minimum list in 40.2) is understood. The initial process specification

limits shall be chosen such that metal integrity parameters are within the capability of the process. The manufacturer shall

have a change control system in place such that new or changed processes are not put into production without the

appropriate reliability evaluation.

40.2 Manufacturing controls

. The manufacturer shall establish manufacturing controls in order to achieve uniformly good

quality and reliability in their metal system, and to assure that the product is being manufactured according to the

assumptions made during design. The manufacturer shall determine which parameters are critical to metal integrity and

control those parameters in accordance with EIA 557. The manufacturer shall be able to demonstrate control of metal

thicknesses, step coverage and cross-sectional areas, metal line width, contact and via sizes, contact and via resistance,

and sheet resistance as a minimum, and show that they are being controlled to limits that are consistent with the way the

metal system was designed. Specification limits shall be established for these parameters. In addition, defects that

threaten metal integrity must be controlled in accordance with the alternate visual procedure (alternate 2) in appendix A of

TM5004.

40.3 Reliability testing

. While it is desirable to design in and build in reliability rather than to achieve reliability by

screening finished product, there is valuable information to be gained from screening and reliability testing. Screening test

such as burn-in not only eliminate the weaker parts in a population, but also provide information on failure mechanisms

which can be used to improve design, materials, processes, or electrical test. Similarly, accelerated testing is used to

speed up failure mechanisms likely to occur under normal operating conditions of a device. These failure mechanisms can

then be analyzed to provide a basis for improvement. Accelerated test that a manufacturer may use to this end include but

are not limited to electromigration testing, life testing, temperature-humidity-bias testing, and temperature cycling.

Structures used in accelerated test must be typical of the technology represented. Failure mechanisms experienced during

accelerated testing must be typical of those experienced during normal use of the device.

MIL-STD-883F

METHOD 2018.4

18 June 2004

APPENDIX A

40.3.1 Reliability evaluating

. The manufacturer must have in place a system for evaluating the reliability of the metal

system. The system shall enable the manufacturer to determine the probability of failure in a given lifetime. The lifetime and

failure rate data of the metal system associated with a given technology shall be made available to the customer. The

manufacturer's systematically collected data must indicate that there is a high probability of meeting the specified lifetimes

and/or failure rates.

50. DOCUMENTATION

NOTE: Certain information considered proprietary may only be available under non-disclosure agreement.

50.1 The manufacturer must have available for customer review controlled reliability rules, layout rules, and current

density for each technology for which this procedure is used. In addition, the manufacturer must have available for review

the method by which the above rules are checked and verified.

50.2 The manufacturer shall be able to demonstrate the manufacturing controls and system for disposition of out of

control occurrences that are in place to control the processes determined critical to metal integrity.

50.3 The manufacturer must have available for customer review any testing performed to evaluate the reliability of the

metal system.

50.4 The manufacturer shall specify the metal lifetime to the customer upon request.

MIL-STD-883F

METHOD 2019.7

07 March 2003

METHOD 2019.7

DIE SHEAR STRENGTH

1. PURPOSE

. The purpose of this test is to determine the integrity of materials and procedures used to attach

semiconductor die or surface mounted passive elements to package headers or other substrates. This determination is

based on a measure of force applied to the die, the type of failure resulting from this application of force (if failure occurs)

and the visual appearance of the residual die attach media and substrate/header metallization.

2. APPARATUS

. The test equipment shall consist of a load-applying instrument with an accuracy of ±5 percent of full

scale or 50 grams, whichever is the greater tolerance. A circular dynamometer with a lever arm or a linear motion force-

applying instrument may be used to apply the force required for testing. The test equipment shall have the following

capabilities:

a. A die contact tool which applies a uniform distribution of the force to an edge of the die (see figure 2019-1). A

compliant (conforming) material (e.g., nail polish, tape, etc.) may be applied to th face of the contact tool to ensue

uniform force distribution on the edge of the die.

b. Provisions to assure that the die contact tool is perpendicular to the die mounting plane of the header or substrate.

c. A rotational capability, relative to the header/substrate holding fixture and the die contact tool, to facilitate line

contact on the edge of the die; i.e., the tool applying the force to the die shall contact the die edge from end-to-end

(see figure 2019-2).

d. A binocular microscope with magnification capabilities of 10X minimum and lighting which facilitates visual

observation of the die and die contact tool interface during testing.

3. PROCEDURE

. The test shall be conducted, as defined herein, or to the test conditions specified in the applicable

specific acquisition document consistent with the particular part construction. All die strength tests shall be counted and the

specific sampling, acceptance, and added sample provisions shall be observed, as applicable.

3.1 Shear strength

. A force sufficient to shear the die from its mounting or equal to twice the minimum specified shear

strength (figure 2019-4), whichever occurs first, shall be applied to the die using the apparatus of 2 above.

NOTE: For passive elements only attached at the end terminations, the area used to determine the force applied shall be

the total area of the mounting surface of the end terminations. An area between and terminations filled with non-adhering

filler shall not be used to determine the force applied. However, any adhering material applied between the end terminations

shall be used in the shear calculation, If the area between end terminations contains an adhering material, then the area of

the adhering material shall be added to the area of the mounting surfaces of the end terminations and that total area shall be

used to determine the force applied.

a. When a linear motion force-applying instrument is used, the direction of the applied force shall be parallel with the

plane of the header or substrate and perpendicular to the die being tested.

b. When a circular dynamometer with a lever arm is employed to apply the force required for testing, it shall be

pivoted about the lever arm axis and the motion shall be parallel with the plane of the header or substrate and

perpendicular to the edge of the die being tested. The contact tooling attached to the lever arm shall be at a proper

distance to assure an accurate value of applied force.

c. The die contact tool shall apply a force gradually from zero to a specified value against an edge of the die which

most closely approximates a 90° angle with the base of the header or substrate to which it is bonded (see figure

2019-3). For rectangular die, the force shall be applied perpendicular to the longer side of the die. When

constrained by package configurations, any available side of the die may be tested if the above options are not

available.

d. After initial contact with the die edge and during the application of force, the relative position of the contact tool

shall not move vertically such that contact is made with the header/substrate or die attach media. If the tool rides

over the die, a new die may be substituted or the die may be repositioned, provided that the requirements of 3.1.c

are met.