HD-7110
Low Temperature Curable Negative PI for Advanced Packaging
Hitachi Chemical DuPont MicroSystems, ltd.
Development Technology Center
HDM20181017-NY-01
HDM Confidential
HD MicroSystems Technology Roadmap
Year
Technology
Wafer size
PKG trend
Materials
for
Packaging
Application
〜2011
28nm
2012
2013
2014
20nm
2015
2016
14/16nm
2017
10nm
8”/12”
Flip Chip, WL-CSP
2018
2019
7nm
Panel
2020
5nm
IoT, 5G
Fan-out, 2.5D, 3D
HD-8820
Aqueous-Posi
Standard
New low temp cure Posi-PBO
Ultra lower temp, Excellent resolution& High aspect ratio,
Excellent chemical resistance, Thick formability, Good adhesion
HD-8851
Enhanced chemical
resistance
AqueousPositive
HD-8930
Low temp cure
Standard
SolventNegative
HD-8940
Improved
adhesion
HD-8961
XP-8961H
XP-8961LP
HD-4000
Low viscosity version for
FOPLP with slit coat
Cu Compatible
HD-4100
XP- : under
development
Solv-Nega
Standard
HD-7010
Flexible
Next
version
New Low temp cure Nega-PI
Ultra low temp cure, High resolution, Wide process
latitude, High CD control capability, Thick formable
HD-7110
Next
version
2
Feature of HD-7110




Solvent developable Negative-tone PI
Curing below 200oC available
Good adhesion performance to Cu
High resolution compared to general negative products
(4um/@5umth)
 Low shrinkage at cure  Lower warpage and flatness
 Good film properties and chemical resistance
 Wide process margin
3
Reliability test in Fan-out package - Test vehicle and 12 inch process [Fabrication process]
Re-configuration
Molding
2nd layer patterning & cure
1st layer coating & cure
Dicing & Solder ball mount
Cu line formation
Mount on board
(with underfill)
[Cross section of test vehicle]
4
Reliability test in Fan-out package - Specification of Test Vehicle -
FOWLP
Substrate
Underfill
Item
Package size (mm)
Package thickness (μm)
Molding compound
Chip size (mm)
Chip thickness (μm)
1st dielectric layer thickness (μm)
2nd dielectric layer thickness (μm)
Cu line thickness (μm)
Solder ball
Ball diameter (μm)
Pin count
Ball pitch (μm)
Material
Size (mm)
Thickness (mm)
Surface finish
Material
Specification
9.6 x 9.6
450
CEL-400ZHF40-MANG (Granule, HCC)
7.3 x 7.3
400
7
7
5
Sn-3.0Ag-0.5Cu
250
336
300
FR-4
17 x 17
0.8
E-less Ni/Au plating
CEL-C-3730-N3 (HCC)
5
Reliability in Fan-out package - TCT results in chip level [Test vehicle]
Solder
Dielectric 2
Dielectric 1
Chip
EMC
[Pictures after reliability test]
Crack
No crack and
no delamination
[Test condition]
•
•
•
Pre-condition : 85ºC/85%RH/168h +
N2 reflow (max.260ºC) 10 times
TCT condition : -65ºC/15min.↔150ºC/15min.
Visual check by microscopy
Conventional
HDM new low temp
cure product
[Result]
TCT cycles
Test results
initial
No crack or delamination
200
No crack or delamination
400
No crack or delamination
600
No crack or delamination
800
No crack or delamination
1000
No crack or delamination
 HD-7110 showed no crack and no delamination until TCT 1000 cycles.
6
Reliability in Fan-out package - TCT results in board level [Test condition]
[Test vehicle]
FO chip
Solder
PCB
•
•
TCT condition : -65ºC/15min.↔150ºC/15min.
Electrical check in daisy chain pattern
[Result]
TCT cycles
initial
200
400
600
800
1000
Cumulative electrical failure rate
(%)
0
0
0
0
0
0
 HD-7110 showed no electrical failure until TCT 1000 cycles.
7
Reliability of PI in Fan-in package after TCT treatment
[Test vehicle]
[Test condition]
WLCSP
Solder
PCB
TCT condition: -50 oC⇔ 125 oC.
WLCSP: 1 Cu RDL, 2 PI layers
Ball mount area: 3.5 x 3.5 mm
Chip size: 10 x 10 mm
[Result]
Conventional PI (375 oC)
Conventional PBO (320 oC)
XP-7100-A2 (200 oC)
 XP-7100-A2, similar composition to HD-7110, showed higher reliability than conventional PI/PBO.
 HD-7110, advanced version, is expected to show same performance or more than that.
8
Moisture resistance - Appearance of Cu electrode after PCT X-section of Cu electrode after PCT 100h
No void, no delamination in all cure conditions
Conventional dielectric material
Structure of test vehicle (X-section)
Delamination
100um
PI
(7um)
P-SiO2
After PCT
20um
Cu electroplated
(5 umth)
Sputtered Cu
Sputtered Ti
Si substrate
PCT condition:121C 100RH% 2atm100h
 Even cure is 175C/2h, no void and no delamination after PCT treatment.
 Good adhesion to Cu in wide cure temperature range(175C-225C).
9
Bias HAST test at fine pitch L/S (L/S= 2/2um)
[Structure of test vehicle]
Cu
4 mm
PI
HD-7110
(200C cure, 7 μm)
L/S=2/2 or 5/5um
Electroplated Cu
(3.5 um )
Sputtered Cu
Top view
Resistance after bias-HAST
1.E+16
Resistance (ohm)
Sputtered Ti
Si substrate
SiO2
X-sectional view
[ Test results ]
[Test condition]
130 degC / 85%RH / 3.3 V DC
1.E+14
Polyimide
2/2um
Appearance and X-section after bias-HAST
(2/2um L/S)
5/5um
1.E+12
1.E+10
1.E+08
Passed 168hr in 2/2um L/S
1.E+06
1.E+04
0
50
100
Test time (h)
150
No migration, No delamination
 HD-7110 also showed good insulation reliability at 2/2 and 5/5 μm.
10
Bias HAST test (L/S=100/20um) -1
[Structure of comb pattern for test]
[Test conditions]






Temperature: 130C
Humidity: 85%RH
Bias: DC6V
Time:500hr
Cu/Cu distance : 20um
Cure condition：175C/2h, 200C/2h
100um
PI
Cu
20um
Electroplated Cu(5 um )
PI
(7um)
Sputtered Cu
Sputtered Ti
Si substrate
P-SiN
Top view
Cross section
[Appearance before & after HAST]
 No appearance change after 500hr of bias-HAST even in 175C cured sample.
11
Bias HAST test with 50V (L/S=100/20um)
[Structure of comb pattern for test]
[Test conditions]






Temperature: 130C
Humidity: 85%RH
Bias: DC50V
Time:138hr
Cu/Cu distance : 20um
Cure condition：200C/2h
100um
PI
Cu
20um
Electroplated Cu(5 um )
PI
(7um)
Sputtered Cu
Sputtered Ti
Si substrate
P-SiN
Top view
Cross section
[Test result]
 HD-7110 showed excellent insulation reliability even at DC 50V.
12
Film properties after PCT treatment
Accelera
tion
Tensile
strength
(MPa)
Elongati
on
(%)
Modulus
(GPa)
w/o
190
39
3.4
w/
140
37
3.1
w/o
177
41
3.3
w/
157
42
3.1
w/o
158
40
2.9
w/
146
36
2.9
175
200
200C cure
No big change of Yield point
Stress(MPa)
Cure
temp.
(C/2h)
225
Strain (%)
Acceleration condition: PCT condition 121C / 2atm / 100 % / 100 h
Measurement tool for this study: SHIMADZU AGS-100NH (Max 100N)
 HD-7110 keeps good mechanical properties after PCT treatment.
 No big change of Yield point is confirmed after PCT treatment.
13
Film properties after HTS test
200/2hr
Elongation
(%)
Modulus
(GPa)
initial
177
41
3.3
150C/500h
159
30
3.0
175C/250h
160
34
3.1
Measurement tool for this study: SHIMADZU AGS100NH (Max 100N)
Stress(MPa)
Acceleration
Strain (%)
No big change of Yield point
Stress(MPa)
Cure
No big change of Yield point
Tensile
strength
(MPa)
Strain (%)
 HD-7110 keeps good mechanical properties after HTS treatment.
14
Chemical resistance
HD-7110
Chemicals
Treatment
conditions
(C/min)
175C/2h
Appearance
1)
200C/2h
Film thick. Appearance
1)
change (%)
HD-4xxx
225C/2h
Film thick. Appearance
1)
change (%)
375C/1h
Film thick. Appearance
1)
change (%)
Film thick.
change (%)
Aceton
25/15
OK
< ±1
OK
< ±1
OK
< ±1
OK
< ±1
NMP
25/30
OK
< ±1
OK
< ±1
OK
< ±1
OK
< ±1
30%H2SO4
25/10
OK
< ±1
OK
< ±1
OK
< ±1
OK
< ±1
2.38% TMAH
25/15
OK
< ±1
OK
< ±1
OK
< ±1
OK
< ±1
Film thickness: 10um
1) “OK” : no-crack, delamination and discoloration
 Good chemical resistance in wide cure temperature range.
15
Chemical resistance (Dynastrip7700)
Film thickness: 10um
Treatment condition : 70C/30min
 No penetration and no delamination even by treatment with dry film stripper like Dynastrip7700
16
Lithographic performance
Resolution
100
20
80
15
60
i-line
B.B
40
Resolution(um)
Film retention (%)
Film retention after development
Prebake:105C/120s+115C/120s
Exposure: i-line stepper
Thickness : 10um after cure
10
5
0
200
20
100
300
500
700
900 1100
Exposure dose (mJ/cm2)
400
600
800
Exposure dose(mJ/cm2)
8um
7um
6um
PB condition:105C/120s+115C/120s
Exposure: i-line stepper or BB aligner
Thick : 10um after cure
Film retention: Developed thickness / Prebaked thickness X100(%)
400mJ/cm2
 More than 500mJ/cm2 is needed to get over 85% film retention.  A little higher exposure dose is needed for HD-7110
compared with general negative PI because sensitivity was controlled to aim high resolution.
 HD-7110 has high resolution in general negative PI.  6um circle pattern is open at 10um thickness
17
Pattern profile after cure
Θ=74°
Θ=74°
Film thickness: 10um after cure
Substrate : Si wafer
 HD-7110 has smooth and no crown pattern profile both 10 um space and 10um via.
18
X-section of fine via patterns
5 μm via w/o plasma treatment
5 μm via w/ plasma treatment
6.3 μm
6.0 μm
74o
62o
2.3 μm
4.1 μm
Irradiation: 500 mJ/cm2.
Cure condition: 200 oC / 2h.
Plasma condition: 200W, 150 sccm, 3 min.
 5 μm via was opened at 5um thickness and 4.1um of CD was obtained clearly by plasma treatment.
19
Pattern profile of HD-7110
Film thickness: 10um after cure
Exposure dose: 500mJ/cm2
 No big change in pattern profile with wide range of cure temperature (175C-225C)
 No significant change in pattern profile even with additional cure.
20
Film thickness change at each process
Item
HD-7110
(@10um thickness)
Unit
HD-4xxx
(Ref)
175C/2h
200C/2h
225C/2h
250C/2h
275C/2h
375C/1h
PB thickness
um
12.7
12.9
13.3
13.5
13.8
22
Developed thickness
um
10.8
11.1
11.4
11.7
12
20.7
Cured thickness
um
10
Film retention (Dev/PB)
%
85
86
86
87
87
94
Film retention (Cure/Dev)
%
93
90
88
85
83
48
Final film retention (Cure/PB)
%
79
78
75
74
72
45
25
Film thickness (um)
PB thick
Developed thick
Cured thick
20
15
10
5
0
175C/2h
200C/2h
225C/2h
250C/2h
XP-7100-B1
275C/2h
375C/1h
HD-4xxx
Cure condition
 HD-7110 keeps higher film retention after development and cure step respectively with
wide cure range.
21
Planarization of HD-7110 series
HD-7110 series
HD-41XX series
Depth=3.6um
Depth 6.7 μm
10um
1st PI layer
10um
Si wafer
Target thickness:10um
Cure conditions: HD-7110 series 225C/1h
HD-4XXX series 375C/1h
 HD-7110 series can planarize deep gap well due to low shrinkage after cure.
 It should be advantage for multiple layer devise with large bumpy surface.
22
Spin coating curve
20
Prebake
Development
Cure
15
Film thickness (um)
Film thickness (um)
20
10
5
Prebake
Development
Cure
15
10
5
0
0
1000
1500
2000
2500
3000
3500
10
Spin speed (X rpm/30sec)
20
30
40
50
60
70
Spin speed time(2000rpm/X sec)
Spin-speed vs Film thickness
PB condition: 105C/120sec + 115C/120sec
Exposure: 500mJ/cm2
Cure: 200C/2h
23
Process margin – Prebake temp. or Dev. time Dev. time vs film retention
Prebake temp. vs film retention
Film retention after Dev. (%)
90
80
70
400mJ/cm2
500mJ/cm2
60
600mJ/cm2
50
100 + 110
105 + 115
110 + 120
Prebake temperature
Film retention after dev. (%)
100
100
90
80
70
400mJ/cm2
60
500mJ/cm2
600mJ/cm2
50
5+5
10+10
15+15
20+20
Development time (sec)
(X℃/120s + Y℃/120s)
Development time=10sec + 10sec
Prebaked thickness=13um
Film retention= PB thickness / Developed thickness x 100(%)
Prebake=105℃/120sec + 115℃/120sec
Prebaked thickness=13um
Film retention= PB thickness / Developed thickness x 100(%)
 Film retention change is a little with shift of prebake or development conditions, which
means wide process margin in photolithographic process.
24
Film properties with different cure temp
Cure temp.
o
C/2h
175
200
225
250
275
300
Tensile strength
MPa
190
177
175
174
179
164
Elongation
%
39
41
40
42
44
39
Young's Modulus
GPa
3.4
3.3
2.9
2.8
2.8
2.8
Tg value (TMA).
C
225
233
233
242
254
262
CTE(100-150C)
ppm/C
63
61
60
59
53
52
5% weight loss temp.
C
317
336
347
347
353
366
Residual stress
MPa
25
25
25
25
25
29
 Keep good film properties in wide cure range
25
Summary
 Low shrinkage at cure process (10% shrinkage)
 Lower stress, warpage and flatness
 High resolution compared to general negative PI
(4um via opening is available.)
 Good Cu adhesion
 Wide process margin
 Good reliability performance
26