IPC CID Exam (Latest 2026 Update) |
Complete Guide with Questions and
Verified Answers | 100% Correct | Grade
A+
• What are the 4 types of build-up multilayers? Answer: Piercing post,
Sequentially built-up multilayer, Passive substrate, Filled via sequential
co-laminated substrate
• The temperature at which anamorphous polymer changes from being a
hard and relatively-brittle condition to be in a viscous or rubbery state
Answer: Glass transition temperature (Tg)
• Affects dimensional stability and changes the electrical characteristic
in the material which can cause potential difficulties in assembly
Answer: Moisture absorption
• What are the 3 general methods of plating material on PCBs? Answer:
Immersion, electroless, and electrolytic
• What are the benefits of metallic coatings / final(surface) finish?
Answer: Corrosion prevention, Improved long-term solderability
• 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 Answer:
Immersion Plating
• Why would you use immersion plating? Answer: The thickness is
limited to a very thin coating as it is a simple replacement reaction
• Why is Immersion finishes more beneficial than HASL? Answer:
Immersion has a flatter base for attachment
• What are the assembly challenges/problems with HASL process?
Answer: Coplanarity / solder thickness varies, solder crowning, less
uniformity
• Stencil fits flat on pad, opening is smaller than the land pattern in all
dimensions Answer: Gasketing
• What is the problem with gasketing in HASL? Answer: Uneven
surfaces cause leakage of paste underneath the stencil
• What other surface finishes are better/flatter than HASL? Answer:
Gray tin, nickel/gold, nickel/palladium gold, immersion "white" tin,
immersion silver, ENIG
• What surface finish is good for BGAs and surface mount? Answer:
ENIG
, • Why would you use a washable solder mask / what is the advantage?
Answer: Washable masks are removable; they come off in a cleaning
operation
• What is plugging? Answer: Process to ensure that plated through holes
are prevent from being contaminated by the assembly cleaning and
plating process chemistries
• For liquid photo imageable masks, what via process does IPC
recommend? Answer: Plugging
• For dry film masks, what via process does IPC recommend? Answer:
Tenting
• What will manufacturers do to get proper flow characteristics of the
prepreg material and gain better performance of the multilayer structure?
Answer: Manufacturers will mix and match the various prepreg products
• For surface mount and for the outer layers to be heat-resistant, what
can the manufacturer do to help this? Answer: Polyimide material can be
used for the outer layers of a multilayer while inner layers are standard
epoxy-grade product
• In terms of material performance capability, how do you achieve
homogenous construction? Answer: Same material is used/only slight
variations occur between different material properties. Resin flow of the
prepreg must be consistent between the layers
Complete Guide with Questions and
Verified Answers | 100% Correct | Grade
A+
• What are the 4 types of build-up multilayers? Answer: Piercing post,
Sequentially built-up multilayer, Passive substrate, Filled via sequential
co-laminated substrate
• The temperature at which anamorphous polymer changes from being a
hard and relatively-brittle condition to be in a viscous or rubbery state
Answer: Glass transition temperature (Tg)
• Affects dimensional stability and changes the electrical characteristic
in the material which can cause potential difficulties in assembly
Answer: Moisture absorption
• What are the 3 general methods of plating material on PCBs? Answer:
Immersion, electroless, and electrolytic
• What are the benefits of metallic coatings / final(surface) finish?
Answer: Corrosion prevention, Improved long-term solderability
• 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 Answer:
Immersion Plating
• Why would you use immersion plating? Answer: The thickness is
limited to a very thin coating as it is a simple replacement reaction
• Why is Immersion finishes more beneficial than HASL? Answer:
Immersion has a flatter base for attachment
• What are the assembly challenges/problems with HASL process?
Answer: Coplanarity / solder thickness varies, solder crowning, less
uniformity
• Stencil fits flat on pad, opening is smaller than the land pattern in all
dimensions Answer: Gasketing
• What is the problem with gasketing in HASL? Answer: Uneven
surfaces cause leakage of paste underneath the stencil
• What other surface finishes are better/flatter than HASL? Answer:
Gray tin, nickel/gold, nickel/palladium gold, immersion "white" tin,
immersion silver, ENIG
• What surface finish is good for BGAs and surface mount? Answer:
ENIG
, • Why would you use a washable solder mask / what is the advantage?
Answer: Washable masks are removable; they come off in a cleaning
operation
• What is plugging? Answer: Process to ensure that plated through holes
are prevent from being contaminated by the assembly cleaning and
plating process chemistries
• For liquid photo imageable masks, what via process does IPC
recommend? Answer: Plugging
• For dry film masks, what via process does IPC recommend? Answer:
Tenting
• What will manufacturers do to get proper flow characteristics of the
prepreg material and gain better performance of the multilayer structure?
Answer: Manufacturers will mix and match the various prepreg products
• For surface mount and for the outer layers to be heat-resistant, what
can the manufacturer do to help this? Answer: Polyimide material can be
used for the outer layers of a multilayer while inner layers are standard
epoxy-grade product
• In terms of material performance capability, how do you achieve
homogenous construction? Answer: Same material is used/only slight
variations occur between different material properties. Resin flow of the
prepreg must be consistent between the layers
