2.1 Glass substrate delamination（4strip）

2.1.1 glass substrateARMembrane detachment

【abnormal phenomenon】glass substrateARLocal or overall detachment of the membrane during use or testing，Adhesion does not meet the standard。

【Root cause analysis】

(1) Insufficient cleanliness of glass surface：grease stain、fingerprint、Dust residue

(2) Hydroxyl groups on glass surface(-OH)Low density，Poor adhesion with oxide film

(3) The coating temperature is too low(<80℃)，Insufficient oxidation of film layer

(4) Insufficient vacuum degree(>10⁻²Pa)，Residual gas pollution film layer

(5) The film layer is too thin(<50nm)，Unable to form continuous coverage

【solution】

Option One（Emergency diagnosis）：

→ tape test(3M 600adhesive tape)：Observe the area of detachment

→ Grid test(ISO 2409)：0-5Grade rating

→ Microscopic observation of detachment interface：Glass side or film side

→ Compare the adhesion of different cleaning processes

Option 2（Process adjustment）：

→ Glass cleaning：NaOH(5%)Ultrasonic cleaning5min+DIwater rinse

→ Increase plasma cleaning：Ar/O2plasma，200W，5min

→ Raise the coating temperature to150-200℃

→ Increase the vacuum degree to≤5×10⁻³Pa

→ Add bottom layer：SiO2(50nm)perhapsTiO2(20nm)

→ Reduce evaporation rate：0.5-1Å/s，Improve membrane density

Option Three（settle sth. once and for all）：

→ Glass surface activation：UV/O3handle30min，Increase hydroxyl density

→ Using ion assisted deposition(IAD)：Improve the adhesion of the film layer

→ Develop a specialized primer layer：Silane coupling agent treatment

→ Establish a standard process for glass cleaning：6Step cleaning method

→ Standardization of adhesion testing：random inspection per batch10%

【preventive measures】

• Glass incoming materials must be inspected for surface cleanliness，contact angle<10°

• Plasma cleaning before coating is an essential process

• Establish a cleaning solution replacement cycle：NaOHSolution is replaced weekly

【Precautions】

⚠ The detached sample cannot be directly reworked，Need to be cleaned again

⚠ Glass cannot be directly touched by hand

2.1.2 Glass substrate laser film delamination

【abnormal phenomenon】High power laser film on glass substrate(1064nm/532nm)Falling off during use，Affects the safety of laser systems。

【Root cause analysis】

(1) There are many laser film layers(>30layer)，Accumulation of interface stress

(2) High power laser irradiation generates thermal stress，Causing membrane fatigue

(3) The difference in thermal expansion coefficient between the film layer and glass is significant(Ta2O5 6.5 vs glass 9)

(4) Laser films are usually thicker(>15μm)，High adhesion requirements

(5) Mechanical damage during laser cleaning or maintenance

【solution】

Option One（Emergency diagnosis）：

→ Laser damage threshold testing：Determine the integrity of the membrane layer

→ microscope observation：Detachment starts from the edge→Stress issue

→  Tapetest：Evaluate adhesion level

→ Compare the delamination situation of different power densities

Option 2（Process adjustment）：

→ Reduce sputtering power：Ta2O5from3W/cm²drop to1.5W/cm²

→ Increase annealing：250℃、N2atmosphere、2h

→ Optimize membrane system design：Reduce the thickness of the high refractive index layer

→ increaseSiO2protective layer：top level200nm

→ Using ion beam sputtering(IBS)：Improve membrane density

→ Glass surface pretreatment：HF(1%)corrosion30s

Option Three（settle sth. once and for all）：

→ Develop a specialized bottom coating for laser films：HfO2Gradient layer

→ Replace ordinary glass with fused silica：Lower coefficient of thermal expansion

→ Design stress balance membrane system：compressive stress+Alternating tensile stress

→ Establish laser film accelerated aging testing standards

→ Each batch of laser film must undergo adhesion testing+Double testing of damage threshold

【preventive measures】

• Laser film glass must be of optical grade，bubble/stripe<Grade 3

• Cleanliness of laser film plating room100level

• Purity of laser film target material>99.99%

【Precautions】

⚠ After the laser film falls off, it cannot be continued to be used，There are safety hazards

⚠ High power laser systems require regular inspection of film integrity

2.1.3 Glass substrate infrared film delamination

【abnormal phenomenon】Glass substrate infrared film(3-5μmperhaps8-14μm)Falling off during use，Affects the performance of infrared systems。

【Root cause analysis】

(1) Infrared film material(ZnS、Ge)Poor adhesion with glass

(2) Infrared film is usually thicker(>10μm)，High adhesion requirements

(3) High temperature for infrared film coating(>200℃)，Changes in the surface state of glass

(4) Infrared film experiences significant temperature fluctuations during use(-40~+80℃)，thermal fatigue

(5) Infrared film surface is prone to adsorb water vapor，Hydrolysis leads to membrane detachment

【solution】

Option One（Emergency diagnosis）：

→ FTIRmeasurement：The area of decreased transmittance corresponds to the location of delamination

→ microscope observation：Peel off starts from the edge or center

→ Boiling test：80℃、30min，Observe the detachment of the film

→ Compare the adhesion of different film materials

Option 2（Process adjustment）：

→ increaseSiO2buffer layer(100nm)：glass/SiO2/Infrared film

→ Reduce the coating temperature to150℃，useIADassistant

→ ZnSevaporativity2-3Å/s，Ge 1Å/s

→ After coating, chargeN2protect，Prevent oxidation

→ Add top protective film：SiO2(50nm)perhapsY2O3(30nm)

→ Before using the infrared film200℃bake2hRemove water vapor

Option Three（settle sth. once and for all）：

→ Develop a specialized primer for infrared films：TiO2/SiO2gradient

→ Using ion beam assisted deposition(IBAD)：Improve adhesion

→ Surface hydrophobic treatment of infrared film：Fluorosilane coating

→ Establish environmental adaptability testing standards for infrared films

→ Apply adhesion to each batch of infrared film+Environmental Testing

【preventive measures】

• Infrared film glass must be selected with lowOH⁻content

• Vacuum degree of infrared film plating chamber≤3×10⁻³Pa

• Infrared film storage requires drying，humidity<40%

【Precautions】

⚠ Infrared film cannot be repaired after detachment

⚠ Infrared film cannot be directly touched by hand

2.1.4 Optical glass large aperture lens delamination

【abnormal phenomenon】Large aperture optical lens(>100mm)Edge or local peeling occurs after coating。

【Root cause analysis】

(1) Stress concentration in the clamping area of the large lens，Edge delamination

(2) The self weight of the lens causes uneven stress in the bottom facial mask layer

(3) Uneven distribution of coating thickness：Center thin, edge thick

(4) Difficulty in cleaning large lenses，Poor edge cleanliness

(5) Uneven temperature distribution during coating：Center high, edge low

【solution】

Option One（Emergency diagnosis）：

→ Observe the detachment position：edge→Clamping or cleaning issues

→ Measure the distribution of film thickness：Stairmeter or ellipsometer

→ Check the fixture：Is there any indentation or contamination

→ Compare the delamination situation of different clamping methods

Option 2（Process adjustment）：

→ Optimize fixture design：Three point flexible support

→ Increase edge occlusion：Mask board protects the edges

→ Improve temperature uniformity：Ring heater

→ Rotation speed during coating：10-30rpm

→ Increase the thickness of the edge film：Adjust the angle of the evaporation source

→ Segmented coating of large lenses：divide2-3Complete next time

Option Three（settle sth. once and for all）：

→ Design specialized large-diameter coating fixtures

→ Using planetary fixtures：Improve the uniformity of film thickness

→ Establish coating process standards for large lenses

→ Special cleaning equipment for large lenses：spray+ultrasound

→ Film thickness distribution of each batch of large lens sampling inspection

【preventive measures】

• The surface quality of incoming large lenses must be inspected

• Special cleaning is required before coating large lenses

• The large lens fixture must be inspected regularly

【Precautions】

⚠ Difficulty in reworking large lenses after detachment

⚠ Special tools are required for handling large lenses

§2.2 Metal substrate delamination（3strip）

2.2.1 Copper substrate decorative film peeling off

【abnormal phenomenon】Copper substrate plated decorative film(Cr、TiN、ZrNclass)Later detachment occurred，hardware、Common problems with decorations and other items。

【Root cause analysis】

(1) CuSurface oxide layer(Cu2O/CuO)Poor adhesion with the membrane layer

(2) CuHigh coefficient of thermal expansion(16.5×10⁻⁶/℃)，High membrane stress

(3) CuLow hardness，Vulnerable to mechanical damage

(4) Decorative film usually contains a metal layer，giveCuEasy to spread

(5) CuLow surface roughness，Weak mechanical locking force

【solution】

Option One（Emergency diagnosis）：

→  Tapetest：Evaluate adhesion

→ scratch test：Observe the peeling morphology

→ EDXanalysis：Is there any oxide present at the interface

→ Compare the adhesion of different surface treatments

Option 2（Process adjustment）：

→ CuSurface acid washing：H2SO4(10%)+HCl(5%)，Remove oxides

→ increaseNibottom layer(50-100nm)：Cu/Ni/decorative film

→ Using magnetron sputtering：Ion bombardment for cleaning surfaces

→ CuSurface roughening：sandblastingRa=0.5-1μm

→ Reduce the coating temperature to<100℃

→ Increase annealing：200℃、30min

Option Three（settle sth. once and for all）：

→ CuSurface chemical platingNi-P(5-10μm)：Complete isolation

→ developmentCuSpecialized decorative film system

→ Adopting multi arc ion plating：High energy ion cleaning

→ establishCuStandard Process for Surface Treatment

→ per batchCuPerform adhesion testing on the piece

【preventive measures】

• CuThe incoming materials must be inspected for the oxide layer

• CuAcid washing is necessary before coating

• CuStorage needs to be dry

【Precautions】

⚠ CuThe detached sample can be reworked，But it needs to be reprocessed

⚠ CuNot suitable for high-temperature coating

2.2.2 Aluminum substrate functional film delamination

【abnormal phenomenon】Aluminum substrate coated with functional film(conduct electricity、reflection、Protection, etc)Later detachment occurred。

【Root cause analysis】

(1) AlSurface oxide layer(Al2O3)dense，Poor adhesion with the membrane layer

(2) AlExtremely high coefficient of thermal expansion(23×10⁻⁶/℃)

(3) AlLow hardness，deformable

(4) AlReacts with many film materials to generate brittle compounds

(5) The influence of alloying elements in aluminum alloys on film growth

【solution】

Option One（Emergency diagnosis）：

→  Tapetest

→ Grid test

→ Observe the detachment interface

→ Compare the adhesion of different alloys

Option 2（Process adjustment）：

→ AlSurface anodizing：generate10-20μm Al2O3

→ increaseTibottom layer(20nm)

→ Using magnetron sputtering

→ AlSurface sandblasting

→ Reduce the coating temperature

→ Control cooling rate

Option Three（settle sth. once and for all）：

→ AlSurface micro arc oxidation

→ developmentAlSpecialized conversion film

→ adoptPVD-Albottom layer

→ establishAlSurface treatment standards

→ per batchAlPerform adhesion testing on the piece

【preventive measures】

• AlThe incoming materials must be inspected for the oxide layer

• AlAnodizing is necessary before coating

• AlNot suitable for long-term exposure to humid environments

【Precautions】

⚠ AlThe detached sample can be reworked

⚠ AlNot suitable for high-temperature coating

2.2.3 Stainless steel substrate film delamination

【abnormal phenomenon】stainless steel(SUS304/316)Peeling occurs after coating，tableware、medical device、Decorations, etc。

【Root cause analysis】

(1) Passivation film on stainless steel surface(Cr2O3)dense

(2) Thermal expansion coefficient of stainless steel(17×10⁻⁶/℃)

(3) Residual stress after stainless steel processing

(4) Stainless steelNi、CrReaction with membrane material

(5) Low surface roughness of stainless steel

【solution】

Option One（Emergency diagnosis）：

→  Tapetest

→ Grid test

→ XPSDetecting passivation film

→ Compare the adhesion of different surface treatments

Option 2（Process adjustment）：

→ Stainless steel pickling：HCl+HNO3

→ increaseCrbottom layer(50nm)

→ Arplasma cleaning：500W、10min

→ Using magnetron sputtering

→ Control the coating temperature<200℃

→ Surface roughening

Option Three（settle sth. once and for all）：

→ Nitriding treatment on stainless steel surface

→ Develop a specialized stainless steel base coating process

→ Adopting multi arc ion plating

→ Establish surface treatment standards for stainless steel

→ Perform adhesion testing on each batch

【preventive measures】

• Stainless steel incoming materials must have the passivation film removed

• Plasma cleaning is necessary before stainless steel coating

• Stainless steel cannot be used for high-temperature coating

【Precautions】

⚠ Stainless steel delamination samples can be reworked

⚠ Stainless steel welded parts require annealing to relieve stress

§2.3 Plastic substrate delamination（3strip）

2.3.1 PMMA/PCSubstrate delamination

【abnormal phenomenon】PMMA、PCAfter the optical plastic coating is applied, it may peel off，eyeglass lens、Protective face shields, etc。

【Root cause analysis】

(1) Plastic surface energy is low(PMMA 40mN/m，PC 42mN/m)

(2) Plastic has a high coefficient of thermal expansion(60-70×10⁻⁶/℃)

(3) Plastic has high internal stress，Injection residue

(4) Plastic surface polarity is low，Poor adhesion with inorganic membranes

(5) Plastic is sensitive to solvents，Restricted cleaning

【solution】

Option One（Emergency diagnosis）：

→  Tapetest

→ Boiling test：80℃、30min

→ Compare the adhesion of different surface energies

→ Check the injection molding process parameters

Option 2（Process adjustment）：

→ PMMA/PCSurface corona treatment：Increase surface energy to50mN/m

→ increaseSiO2bottom layer(30-50nm)

→ Adopting plasma cleaning：Ar/O2

→ Reduce the coating temperature to room temperature

→ Control film thickness<300nm

→ Using sputtering instead of evaporation

Option Three（settle sth. once and for all）：

→ PMMA/PCsurfaceUVCuring treatment

→ Developing a low stress film system specifically for plastics

→ Using plasma polymerization as a base material

→ Establish plastic coating process standards

→ Apply adhesion to each batch+Boiling test

【preventive measures】

• Plastic incoming materials must undergo surface energy testing

• Before plastic coating, corona treatment is necessary

• Plastic storage should avoid internal stress

【Precautions】

⚠ Plastic delamination samples cannot be reworked

⚠ Plastic should not come into contact with organic solvents

2.3.2 PETThin film delamination

【abnormal phenomenon】PETThin film coating(block、conduct electricity、Decoration, etc)Later detachment occurred，package、Electronic and other fields。

【Root cause analysis】

(1) PETLow surface energy(about40mN/m)

(2) PETThin membrane(12-250μm)，deformable

(3) Roll to roll(R2R)Improper control of coating tension

(4) PETrightUVsensitive，Surface treatment is limited

(5) PETLow surface roughness

【solution】

Option One（Emergency diagnosis）：

→  Tapetest

→ measurementR2RZhang Li

→ Comparing adhesion under different tensions

→ Check the surface treatment effect

Option 2（Process adjustment）：

→ PETcorona treatment：Increase surface energy to50mN/m

→ controlR2RZhang Li：50-100N/m

→ Increase plasma cleaning

→ Using sputtering

→ Control the winding tension<unwinding tension

→ Add guide rollers

Option Three（settle sth. once and for all）：

→ PETSurface plasmon polymerization

→ developmentR2RSpecialized low stress film system

→ adoptALDtechnology

→ establishR2RCoating process standards

→ Perform adhesion testing on each batch

【preventive measures】

• PETThe surface energy of incoming materials must be inspected

• R2REquipment tension must be calibrated

• PETStorage should avoid wrinkles

【Precautions】

⚠ PETThe detached sample cannot be reworked

⚠ PETThe roll should not be too tight

2.3.3 PI(polyimide)Substrate delamination

【abnormal phenomenon】PIFalling off after thin film coating，Flexible circuit、Flexible display and other fields。

【Root cause analysis】

(1) PILow surface energy(about40mN/m)

(2) PIGood temperature resistance but low surface activity

(3) PIWater absorption rate is about1.5%，Water vapor affects adhesion

(4) PIcoefficient of thermal expansion(20×10⁻⁶/℃)Significant difference from inorganic membranes

(5) PILow surface roughness

【solution】

Option One（Emergency diagnosis）：

→  Tapetest

→ Boiling test

→ Compare the adhesion of different surface treatments

→ checkPIwater content

Option 2（Process adjustment）：

→ PISurface plasma cleaning：Ar/O2，Increase activity

→ PIprebake ：150℃、2h，remove moisture

→ increaseSiO2bottom layer(20nm)

→ Using sputtering orALD

→ Reduce the coating temperature to<200℃

→ Control film thickness<200nm

Option Three（settle sth. once and for all）：

→ PISurface plasmon polymerization

→ developmentPISpecialized low stress film system

→ Using sol-Gel priming

→ establishPICoating process standards

→ Apply adhesion to each batch+bend test

【preventive measures】

• PIIncoming materials must be inspected for moisture content

• PIPre baking is necessary before coating

• PIStorage needs to be dry

【Precautions】

⚠ PIThe detached sample cannot be reworked

⚠ PINot suitable for long-term exposure to humid environments

§2.4 Other substrate delamination（3strip）

2.4.1 Ceramic substrate delamination

【abnormal phenomenon】ceramics(Al2O3、ZrO2、Si3N4)After coating the substrate, detachment occurs。

【Root cause analysis】

(1) Low surface roughness of ceramics，Ra<0.1μm

(2) Chemical inertness of ceramic surface，Weak reaction with membrane layer

(3) There is a significant difference between the thermal expansion coefficient of ceramics and the membrane material

(4) Ceramic porous，Surface adsorbed gas

(5) Microcracks on the surface of ceramics after processing

【solution】

Option One（Emergency diagnosis）：

→  Tapetest

→ Grid test

→ SEMObservation interface

→ Compare the adhesion of different surface treatments

Option 2（Process adjustment）：

→ Ceramic surface roughening：sandblastingRa=0.5-1μm

→ Increase plasma cleaning：Ar，500W

→ Using magnetron sputtering

→ increaseTibottom layer(50nm)

→ Raise the coating temperature to200-300℃

→ Control cooling rate

Option Three（settle sth. once and for all）：

→ Chemical treatment of ceramic surface：HFcorrosion

→ Develop ceramic specific membrane system

→ Adopting multi arc ion plating

→ Establish ceramic surface treatment standards

→ Perform adhesion testing on each batch

【preventive measures】

• Ceramic incoming materials must be inspected for surface roughness

• Ceramic coating must be roughened before coating

• Ceramic storage requires drying

【Precautions】

⚠ Ceramic delamination samples can be reworked

⚠ Ceramics cannot be used for high temperatures(>500℃)Coating

2.4.2 quartz/Fused silica film removal

【abnormal phenomenon】quartz(SiO2)Or fused silica substrate falls off after coating，High precision optical components。

【Root cause analysis】

(1) Quartz has an extremely low coefficient of thermal expansion(0.5×10⁻⁶/℃)，There is a significant difference from the film material

(2) Low hydroxyl density on the surface of quartz

(3) Quartz has high hardness but high brittleness

(4) Quartz surface is super smooth(Ra<0.2nm)，poor adhesion

(5) Quartz is temperature sensitive，Easy to crack under thermal shock

【solution】

Option One（Emergency diagnosis）：

→  Tapetest

→ Grid test

→ Compare the adhesion of different surface treatments

→ Check the surface quality of quartz

Option 2（Process adjustment）：

→ Quartz surface activation：UV/O3handle

→ increaseSiO2bottom layer(50nm)

→ Using ion assisted deposition

→ Raise the coating temperature to200-300℃

→ Reduce the evaporation rate to0.3Å/s

→ Control cooling rate<2℃/min

Option Three（settle sth. once and for all）：

→ Chemical treatment of quartz surface：HF(1%)

→ Developing a low stress film system specifically for quartz

→ Using ion beam sputtering

→ Establish quartz coating process standards

→ Perform adhesion testing on each batch

【preventive measures】

• Quartz incoming materials must undergo surface quality inspection

• Activation treatment is necessary before quartz coating

• Quartz storage should avoid thermal shock

【Precautions】

⚠ Quartz delamination samples cannot be reworked

⚠ Quartz cannot be used for high temperatures(>300℃)Coating

2.4.3 Rework coating and delamination

【abnormal phenomenon】Products that have already been coated may peel off after rework and re coating。

【Root cause analysis】

(1) Residual original film layer，Complex surface state

(2) The adhesion between the old film layer and the substrate has decreased

(3) Damaged substrate during chemical removal of old film

(4) Surface scratches during mechanical removal of old film

(5) Multiple coatings lead to stress accumulation

【solution】

Option One（Emergency diagnosis）：

→ Check if the old film has been completely removed

→ Observe whether the surface of the substrate is damaged

→ Compare the adhesion between the first coating and rework

→ Check the number of rework times

Option 2（Process adjustment）：

→ Thoroughly remove the old film：chemistry+Mechanical Union

→ Reprocess the substrate before rework：polishing+clean

→ Reduce the temperature of rework coating

→ Increase the thickness of the bottom layer

→ Control the frequency of rework≤2time

→ Add annealing after rework

Option Three（settle sth. once and for all）：

→ Develop non-destructive film removal technology：Laser peeling

→ Establish rework process standards

→ Separate batch management for reworked products

→ Establish a limit on the number of rework attempts

→ Perform adhesion testing on each batch of reworked products

【preventive measures】

• Rework products must be thoroughly stripped of the film

• The number of rework times cannot exceed2time

• Rework products need to be separately labeled

【Precautions】

⚠ The adhesion of reworked products is usually lower than that of the first time

⚠ Multiple reworked products are recommended to be scrapped