Low Temperature Curable Positive Tone Photosensitive Polyimide Photoneece LT series Toray Industries, Inc. 1
The features of LT series (1) Low temperature curable ( ~170 ) Less damage for weak semiconductor device by its low thermal budget (2) Extreme low residual stress (13MPa) and low shrinkage during curing (5 ~10%) (3) Alkali developable (2.38%TMAH solution can be used) (4) Physical properties of LT series are same as those of conventional photosensitive polyimide (5) Good resistance to bump or WLP process chemicals (6) Fine patterning resolution (~3um, aspect ratio is about 2) (7) Pattern profile suitable for WLP (re-wiring) process Cure condition( h) 170 X 1 X-section Tensile strength 100Mpa Film propertie s Elongation 30% Young s modulus 2.5GPa (THK:5um) Residual stress 13MPa 2
The film properties and pattern profile vs curing temperature Curing condition( h) 170 X 1 200 X 1 250 X 1 Film propertie s Tensile strength 100MPa 100MPa 102MPa Elongation 30% 20% 20% Young s modulus Residual stress 2.5GPa 2.6GPa 2.8GPa 13MPa 13MPa 25MPa < Sample preparation > Pre-baking : 120 180sec. : 200-600mJ/cm2 (i-line stepper) : 30sec 2Puddles by TMAH 2.38% Curing : 170~250 1h 170 1h 200 1h 250 1h 3um 3um 3um 5um 5um 5um (The film thickness after curing :5μm) 3
Heat stability, chemical resistance Heat stability (outgas) Curing condition 180-1h Quantity of outgas (RT- 300 ) 174ppm Heat stability(pattern profile) 200 cured 300 treatment in Air 200-1h 250-1h 89.3ppm 58.6ppm measured by temperature prograumed desorption MS (TPD-MS) 200 cured Chemical resistance Non-electric Au plating Chemicals treatments Heat stability+chemical resistance 200 cured Flux treatment (300 10min) Low out gas during solder process, no pattern shape change, good chemical resistance 4
T/C Test (X-section) Solder bump Solder: M705-BPS3-T5H (Sn-Ag-Cu) (Senju Metal Industry) UBM (non electrolytic plating) Ni/Au (3um/0.05um) Cu 4μm Ti barrier metal ILD-2 LT (7um) ILD-1 LT (7um) Base layer (7um) PV (p-sin) 500nm Si substrate Scribe line The curing temp. of ILD : 200 ( Time is 1 hour) 5
Package manufacture and T/C test condition Daisy chain Cu Die PSPI 1 a b c d e f g h i j k l m 14 about 14.0 Ω interposer a 1 m 14 k j < Condition for Packaging > 1) Flux process Flux : WS600 (Cookson Electronics) The peak temp. of reflow : 260 10sec. Cleaner : WS-2104 (Kaken Tech) 70 15min Rinser : ST-05 ((Kaken Tech) 20-23 30min 2) The peak temp. of solder reflow : 260 10sec. 3) Underfill : U8437-2 (Namics) The stage temp. of injection : 70-90 The temp. of curing : 165 60min < Thermal cycle > -40~125 (each 15min ) with monitoring the resistance of daisy chain b c d l g i e f h 6
Result of T/C test PSPI LT-6100 LT-6600 PWseries Curing temp. 200 280 160 170 180 280 T / C 0 0/15 0/15 0/15 0/15 0/15 0/15 50 0/15 0/15 0/15 0/15 0/15 0/15 100 0/15 0/15 0/15 0/15 0/15 0/15 150 0/15 0/15 0/15 0/15 0/15 0/15 200 0/15 0/15 0/15 0/15 0/15 0/15 300 0/15 0/15 0/15 0/15 0/15 0/15 500 0/15 0/15 0/15 0/15 0/15 0/15 650 0/15 0/15 0/15 0/15 0/15 0/15 There is no fail(open) under 650 cycle of T/C test. 7
Technical Data 8
LT-series Film properties Tensile strength Elogation Young's modulus CTE Residual stress 5% weight loss temp. Tg (TMA) Dielectric constant Volume resistance Surface resistance Breakdown voltage Water absorption LT-6100 LT-6300 LT-6500 LT-6600 High Low stress Low stress photosensiti High Tg type and slightly type vity type high Tg MPa(200 ) 100 110 121 112 170 cure % 30 30 30 30 200 cure % 20 20 20 20 250 cure % 20 20 20 20 GPa(200 ) 2.6 2.6 3.4 2.9 ppm/ (200 ) 70 61 65 60 170 cure MPa 13 13 21 13 200 cure MPa 13 21 35 20 250 cure MPa 25 23 39 26 200 cure 382 374 393 367 250 cure 388 380 412 371 200 cure 160 180 232 194 250 cure - 201 287 212 (200 ) 3.7 3.4 3.1 3.4 Ωcm >10^16 >10^16 >10^16 >10^16 Ω/ >10^16 >10^16 >10^16 >10^16 kv/mm >420 395 >420 >420 %(200 ) 1.7 1.3 1.1 1.6 9
LT-series Photo process Process performance Chemical resistance Coat Prebake PEB Develop Cure Solvent Resist stripper Alkakine Etchant LT-6100 LT-6300 LT-6500 LT-6600 without HMDS spin /min 120/2.5 3um mj/cm2 200 150 200 200 5um mj/cm2 300 250 300 300 7um mj/cm2 600 550 650 600 9um mj/cm2 1200 900 1400 1200 Not required sec 20-120 /min 170-250/30-120 NMP PGME EL IPA TOK106 25%NaOH 2.38%TMAH H2SO4/H2O2 1%HF rt/15min rt/15min rt/15min rt/15min rt/15min rt/15min rt/5min rt/5min rt/5min no change no change no change no change no change no change no change no change no change 10
Spin curve of LT series < Sample preparation > Substrate : Bare Si Prebake : 120 180sec Spin coat : Clean Track ACT8 (TEL) The film thickness ( mm) 12.0 11.0 10.0 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 LT-6100 LT-6300 LT-6500 LT-6600 0 500 1000 1500 2000 2500 3000 3500 4000 Rotation speed X (rpm) 11
Coating recipe of LT series STEP Time(s) Rotation(rpm Accel Dispense Arm1 Arm2 1 1.0 0 10000 0 1 center NW home 2 15.0 50 100 1 1 center NW home 3 3.0 0 10000 0 1 center NW home 4 1.0 400 200 0 1 center NW home 5 2.0 1000 500 0 1 home NW home 6 25.0 X 10000 0 1 home NW home 7 5.0 X 10000 0 1 home NW in 8 1.0 100 10000 6 1 home NW in 9 10.0 1000 10000 5,6 1 home NW in 10 2.0 800 10000 6 1 home NW in 11 10.0 800 10000 1 home NW home 12 1.0 0 10000 1 home NW home Film thickness is controled in step 6,7.(Main speed; Xrpm) Edge rince flow rate:10ml/min Back rince flow rate:70ml/min Dispence No. 1:PI dispence 5:back rince(ebr7030) 6:edge rince(ebr7030) 12
The patterning process of LT-6100 < 3um > Spincoat X: 3800rpm Pre-baking 120 o C 180sec. (DHP) (Thickness after pre-baking :4.55 um) 150 mj/cm2 (ghi-line Aligner) / 200 mj/cm 2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :3.23 um) Curing 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :2.98um) < 5um > Spincoat Pre-baking Curing < 7um > Spincoat Pre-baking Curing < 9um> Spincoat Pre-baking Curing X: 2000rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :6.53 um) 200 mj/cm 2 (ghi-line Aligner) / 300 mj/cm2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :5.32 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :4.98um) X: 1400rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :8.72 um) 300 mj/cm 2 (ghi-line Aligner) / 600 mj/cm2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :7.51 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :7.03um) X: 1050rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :10.88 um) 350 mj/cm 2 (ghi-line Aligner) / 1200 mj/cm2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :9.65 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :9.04um) 13
Pattern profile of LT-6100 <Sample preparation> Substrate Prebake Cure : Bare Si : 120 180sec : 500mJ/cm2 (i-line stepper) : 30sec 2Puddle : 50C 110C 30min 170 ~250C 1h (3.5C/min) Cure:170 Cure:200 Cure:250 Pattern size 10um >100um 14
The patterning process of LT-6300 < 3um > Spincoat X: 3600rpm Pre-baking 120 o C 180sec. (DHP) (Thickness after pre-baking :4.75 um) 75 mj/cm2 (ghi-line Aligner) / 150 mj/cm 2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :3.20 um) Curing 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :2.98um) < 5um > Spincoat Pre-baking Curing < 7um > Spincoat Pre-baking Curing < 9um> Spincoat Pre-baking Curing X: 2000rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :6.87 um) 100 mj/cm 2 (ghi-line Aligner) / 250 mj/cm2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :5.36 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :5.00um) X: 1350rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :9.02 um) 200 mj/cm 2 (ghi-line Aligner) / 550 mj/cm2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :7.49 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :7.04um) X: 1000rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :11.16 um) 300 mj/cm 2 (ghi-line Aligner) / 900 mj/cm2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :9.65 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :8.91um) 15
Pattern profile of LT-6300 <Sample preparation> Substrate Prebake Cure : Bare Si : 120 180sec : 500mJ/cm2 (i-line stepper) : 30sec 2Puddle : 50C 110C 30min 170 ~250C 1h (3.5C/min) Cure:170 Cure:200 Cure:250 Pattern size 10um >100um 16
The patterning process of LT-6500 < 3um > Spincoat X: 3600rpm Pre-baking 120 o C 180sec. (DHP) (Thickness after pre-baking :4.91 um) 75 mj/cm2 (ghi-line Aligner) / 200 mj/cm 2 (i-line stepper) 45 sec. 2 Puddle development (Thickness after development :3.22 um) Curing 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :3.00um) < 5um > Spincoat Pre-baking Curing < 7um > Spincoat Pre-baking Curing < 9um> Spincoat Pre-baking Curing X: 2000rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :7.12 um) 100 mj/cm 2 (ghi-line Aligner) / 300 mj/cm2 (i-line stepper) 45 sec. 2 Puddle development (Thickness after development :5.42 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :5.08um) X: 1400rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :9.17 um) 250 mj/cm 2 (ghi-line Aligner) / 650 mj/cm2 (i-line stepper) 45 sec. 2 Puddle development (Thickness after development :7.41 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :6.95um) X: 1000rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :11.33 um) 400 mj/cm 2 (ghi-line Aligner) / 1400 mj/cm2 (i-line stepper) 45 sec. 2 Puddle development (Thickness after development :9.66 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :9.02um) 17
Pattern profile of LT-6500 <Sample preparation> Substrate Prebake Cure : Bare Si : 120 180sec : 500mJ/cm2 (i-line stepper) : 45sec 2Puddle : 50C 110C 30min 170 ~250C 1h (3.5C/min) Cure:170 Cure:200 Cure:250 Pattern size 10um >100um 18
The patterning process of LT-6600 < 3um > Spincoat X: 3800rpm Pre-baking 120 o C 180sec. (DHP) (Thickness after pre-baking :4.35 um) 75 mj/cm2 (ghi-line Aligner) / 200 mj/cm 2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :3.20 um) Curing 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :2.97um) < 5um > Spincoat Pre-baking Curing < 7um > Spincoat Pre-baking Curing < 9um> Spincoat Pre-baking Curing X: 2000rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :6.50 um) 100 mj/cm 2 (ghi-line Aligner) / 300 mj/cm2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :5.34 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :4.96um) X: 1500rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :8.66 um) 200 mj/cm 2 (ghi-line Aligner) / 600 mj/cm2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :7.52 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :6.98um) X: 1100rpm 120 o C 180sec. (DHP) (Thickness after pre-baking :10.88 um) 350 mj/cm 2 (ghi-line Aligner) / 1200 mj/cm2 (i-line stepper) 30 sec. 2 Puddle development (Thickness after development :9.72 um) 50 + 110 o C for 30min+ 200 o C for 60min (N 2 ) (Thickness after curing :9.03um) 19
Pattern profile of LT-6600 <Sample preparation> Substrate Prebake Cure : Bare Si : 120 180sec : 500mJ/cm2 (i-line stepper) : 30sec 2Puddle : 50C 110C 30min 170 ~250C 1h (3.5C/min) Cure:170 Cure:200 Cure:250 Pattern size 10um >100um 20
The adhesion strength test between PSPI and Substrate < Test condition > < Test condition > Equipment : Shear tester series 4000 Load cell : BS250 Test speed : 100um/sec. Height of rod from substrate : 5um Sub Sub PSPI 21
LT6100 adhesion strength Cure Temp\Substrate Cu SiO SiN Si 200 76.1 68.2 72.5 83.5 210 69.9 60.8 73.2 65.5 230 82.1 77.1 69.9 69.3 250 81.0 60.7 80.9 78.1 (MPa) LT6100 Adhesion strength (MPa) 100 90 80 70 60 50 40 30 20 10 0 Cu SiO SiN Si 200 210 230 250 22
LT6300 adhesion strength Cure Temp\Substrate Cu SiO SiN Si 200 74.4 76.9 92.7 71.3 210 81.2 95.0 83.1 70.5 230 82.3 87.5 82.6 79.5 250 87.3 88.6 94.1 76.1 (MPa) LT6300 Adhesion strength (MPa) 100 90 80 70 60 50 40 30 20 10 0 Cu SiO SiN Si 200 210 230 250 23
LT6500 adhesion strength Cure Temp\Substrate Cu SiO SiN Si 200 50.0 71.7 58.7 74.7 210 46.8 82.8 70.0 69.0 230 42.7 83.2 61.8 84.0 250 52.1 74.1 77.0 73.4 (MPa) LT6500 Adhesion strength (MPa) 100 90 80 70 60 50 40 30 20 10 0 Cu SiO SiN Si 200 210 230 250 24
LT6600 adhesion strength Cure Temp\Substrate Cu SiO SiN Si 200 60.4 73.5 61.4 62.7 210 62.5 68.8 70.5 63.3 230 64.5 75.7 78.8 66.7 250 83.3 79.7 77.2 76.8 (MPa) LT6600 Adhesion strength (MPa) 100 90 80 70 60 50 40 30 20 10 0 Cu SiO SiN Si 200 210 230 250 25
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