IPC CID+ Exam 2025 Questions and
Answers 100% Pass
dielectric constant and the loss tangent - ✔✔The board material has significant influence
on the electrical performance of the circuit from what two effects?
Piercing post, Sequentially built-up multilayer, Passive substrate, Filled via sequential
co-laminated substrate - ✔✔What are the 4 types of build-up multilayers?
Glass transition temperature (Tg) - ✔✔The temperature at which anamorphous
polymer changes from being a hard and relatively-brittle condition to be in a viscous or
rubbery state
Moisture absorption - ✔✔Affects dimensional stability and changes the electrical
characteristic in the material which can cause potential difficulties in assembly
Immersion, electroless, and electrolytic - ✔✔What are the 3 general methods of plating
material on PCBs?
Corrosion prevention, Improved long-term solderability - ✔✔What are the benefits of
metallic coatings / final(surface) finish?
Immersion Plating - ✔✔Simplest of the wet processes; involves a simple galvanic
replacement reaction; the more noble metal in the solution picks up electrons from the
less noble metal immersed in the solution and plates out
COPYRIGHT © 2025 BY GRACE AMELIA, ALL RIGHTS RESERVED 1
,The thickness is limited to a very thin coating as it is a simple replacement reaction -
✔✔Why would you use immersion plating?
Immersion has a flatter base for attachment - ✔✔Why is Immersion finishes more
beneficial than HASL?
Coplanarity / solder thickness varies, solder crowning, less uniformity - ✔✔What are
the assembly challenges/problems with HASL process?
Gasketing - ✔✔Stencil fits flat on pad, opening is smaller than the land pattern in all
dimensions
Uneven surfaces cause leakage of paste underneath the stencil - ✔✔What is the problem
with gasketing in HASL?
Gray tin, nickel/gold, nickel/palladium gold, immersion "white" tin, immersion silver,
ENIG - ✔✔What other surface finishes are better/flatter than HASL?
ENIG - ✔✔What surface finish is good for BGAs and surface mount?
Washable masks are removable; they come off in a cleaning operation - ✔✔Why would
you use a washable solder mask / what is the advantage?
Process to ensure that plated through holes are prevent from being contaminated by the
assembly cleaning and plating process chemistries - ✔✔What is plugging?
Plugging - ✔✔For liquid photo imageable masks, what via process does IPC
recommend?
Tenting - ✔✔For dry film masks, what via process does IPC recommend?
Manufacturers will mix and match the various prepreg products - ✔✔What will
manufacturers do to get proper flow characteristics of the prepreg material and gain
better performance of the multilayer structure?
COPYRIGHT © 2025 BY GRACE AMELIA, ALL RIGHTS RESERVED 2
, Polyimide material can be used for the outer layers of a multilayer while inner layers
are standard epoxy-grade product - ✔✔For surface mount and for the outer layers to be
heat-resistant, what can the manufacturer do to help this?
Same material is used/only slight variations occur between different material
properties. Resin flow of the prepreg must be consistent between the layers - ✔✔In
terms of material performance capability, how do you achieve homogenous
construction?
Differences in overall resin content and the use of different styles of glass cloth; more
resin/glass content can produce the same external thickness - ✔✔What variation in
construction change the physical and electrical performance of pcbs?
SPC (Statistical Process Control) - ✔✔Integral part of the manufacturing and testing
process; considered in all aspects during the manufaturing process and NOT confined
to an evaluation at the end of the line
In-process coupon evaluation may be cross-sectioned and evaluated; first article
inspection may be performed to ensure the remainder of the lot would be in
conformance - ✔✔What is an example of an SPC?
Test coupons / specimens - ✔✔These specimens are representative of a the product
produced and must represent the process
Provides a systematic path for continuous improvement, identifies root causes of
problems, reduces the number of evaluations that need to be made at the end of the
production cycle - ✔✔What is the purpose of in-process test coupons?
Test coupon AB/R evaluation - ✔✔Hole solderability, thermal stress, plating thickness,
layer registration, anything related to hole condition within a 2-sided/multilayer board
COPYRIGHT © 2025 BY GRACE AMELIA, ALL RIGHTS RESERVED 3
Answers 100% Pass
dielectric constant and the loss tangent - ✔✔The board material has significant influence
on the electrical performance of the circuit from what two effects?
Piercing post, Sequentially built-up multilayer, Passive substrate, Filled via sequential
co-laminated substrate - ✔✔What are the 4 types of build-up multilayers?
Glass transition temperature (Tg) - ✔✔The temperature at which anamorphous
polymer changes from being a hard and relatively-brittle condition to be in a viscous or
rubbery state
Moisture absorption - ✔✔Affects dimensional stability and changes the electrical
characteristic in the material which can cause potential difficulties in assembly
Immersion, electroless, and electrolytic - ✔✔What are the 3 general methods of plating
material on PCBs?
Corrosion prevention, Improved long-term solderability - ✔✔What are the benefits of
metallic coatings / final(surface) finish?
Immersion Plating - ✔✔Simplest of the wet processes; involves a simple galvanic
replacement reaction; the more noble metal in the solution picks up electrons from the
less noble metal immersed in the solution and plates out
COPYRIGHT © 2025 BY GRACE AMELIA, ALL RIGHTS RESERVED 1
,The thickness is limited to a very thin coating as it is a simple replacement reaction -
✔✔Why would you use immersion plating?
Immersion has a flatter base for attachment - ✔✔Why is Immersion finishes more
beneficial than HASL?
Coplanarity / solder thickness varies, solder crowning, less uniformity - ✔✔What are
the assembly challenges/problems with HASL process?
Gasketing - ✔✔Stencil fits flat on pad, opening is smaller than the land pattern in all
dimensions
Uneven surfaces cause leakage of paste underneath the stencil - ✔✔What is the problem
with gasketing in HASL?
Gray tin, nickel/gold, nickel/palladium gold, immersion "white" tin, immersion silver,
ENIG - ✔✔What other surface finishes are better/flatter than HASL?
ENIG - ✔✔What surface finish is good for BGAs and surface mount?
Washable masks are removable; they come off in a cleaning operation - ✔✔Why would
you use a washable solder mask / what is the advantage?
Process to ensure that plated through holes are prevent from being contaminated by the
assembly cleaning and plating process chemistries - ✔✔What is plugging?
Plugging - ✔✔For liquid photo imageable masks, what via process does IPC
recommend?
Tenting - ✔✔For dry film masks, what via process does IPC recommend?
Manufacturers will mix and match the various prepreg products - ✔✔What will
manufacturers do to get proper flow characteristics of the prepreg material and gain
better performance of the multilayer structure?
COPYRIGHT © 2025 BY GRACE AMELIA, ALL RIGHTS RESERVED 2
, Polyimide material can be used for the outer layers of a multilayer while inner layers
are standard epoxy-grade product - ✔✔For surface mount and for the outer layers to be
heat-resistant, what can the manufacturer do to help this?
Same material is used/only slight variations occur between different material
properties. Resin flow of the prepreg must be consistent between the layers - ✔✔In
terms of material performance capability, how do you achieve homogenous
construction?
Differences in overall resin content and the use of different styles of glass cloth; more
resin/glass content can produce the same external thickness - ✔✔What variation in
construction change the physical and electrical performance of pcbs?
SPC (Statistical Process Control) - ✔✔Integral part of the manufacturing and testing
process; considered in all aspects during the manufaturing process and NOT confined
to an evaluation at the end of the line
In-process coupon evaluation may be cross-sectioned and evaluated; first article
inspection may be performed to ensure the remainder of the lot would be in
conformance - ✔✔What is an example of an SPC?
Test coupons / specimens - ✔✔These specimens are representative of a the product
produced and must represent the process
Provides a systematic path for continuous improvement, identifies root causes of
problems, reduces the number of evaluations that need to be made at the end of the
production cycle - ✔✔What is the purpose of in-process test coupons?
Test coupon AB/R evaluation - ✔✔Hole solderability, thermal stress, plating thickness,
layer registration, anything related to hole condition within a 2-sided/multilayer board
COPYRIGHT © 2025 BY GRACE AMELIA, ALL RIGHTS RESERVED 3
