Thermo-Mechanical Deformation and Stress Analysis of Flip-Chip Ball Grid Array
kent Kelly SarahEllenNina
XI 1 1-1 1 1-2 2 1-2-1 IC 4 1-2-2 5 1-3 7 1-4 8 1-5 10 16 2-1 (Shadow Moiré) 16 2-1-1 16 2-1-2 17 2-1-3 18 I
2-2 19 2-3 20 26 3-1 26 3-2 27 3-3 30 3-3- 1 31 3-3- 2 32 42 4-1 42 4-2 42 4-3 ANSYS 43 4-3-1 ANSYS 44 4-3-2 47 58 5-1 58 5-2 61 5-2-1 61 5-2-2 62 II
5-2-3 63 5-3 FCBGA 63 5-3-1 64 5-3-2 65 5-3-3 68 101 6-1 101 6-2 102 103 III
2-1 22 3-1 Anand model 37 4-1 48 4-2 E 49 4-3 BKIN 49 4-4 Creep. 50 4-5 Anand 50 5-1 E 69 5-2 CTE1 69 5-3 /.. 70 5-4 70 5-5 71 5-6 E.. 71 5-7 CTE1... 71 5-8 /.. 72 5-9.. 72 5-10 72 IV
1-1 11 1-2 11 1-3 IC. 12 1-4...... 12 1-5.... 13 1-6 C4 13 1-7 UBM 14 1-8 15 2-1 23 2-2 23 2-3 24 2-4... 24 2-5... 25 2-6.. 25 2-7 3D.... 25 3-1 i.38 3-2 i+1.38 V
3-3.39 3-4 - 39 3-5 Hardening rules 40 3-6 von Mises.40 3-7 Isotropic Hardening 41 3-8 Kinematic Hardening 41 4-1 (a) (b) (c) 51 4-2.52 4-3 (a) (b) 52 4-4 E 53 4-5 BKIN 53 4-6 54 4-7 ANSYS... 55 4-8 8.. 56 4-9 (a) (b) (c) 56 4-10...... 57 5-1 (a) 73 5-1 (b) 73 5-2 UA02 3D...... 74 VI
5-3 (a) 75 5-3 (b) 75 5-4 (a) UA02 76 5-4 (b) UA02 76 5-5 (a) UA03 77 5-5 (b) UA03 77 5-6 (a) UA04 78 5-6 (b) UA04 78 5-7 (a) UA02 79 5-7 (b) UA02 79 5-8 (a) UA03 80 5-8 (b) UA03 80 5-9 (a) UA04 81 5-9 (b) UA04 81 5-10 (a) (D/UF ) 82 5-10 (b) (D/UF ) 82 5-10 (c) (D/UF ) 83 5-11 FCBGA 83 5-12 (a) (D/UF ) 84 VII
5-12 (b) (D/UF ) 84 5-13 (a) FCBGA 85 5-13 (b) FCBGA 85 5-14 (a) E (D/UF ) 86 5-14 (b) E (D/UF ) 86 5-15 FCBGA 87 5-16 E FCBGA 87 5-17 FCBGA 88 5-18 E FCBGA 88 5-19 (a) CTE1 (D/UF ) 89 5-19 (b) CTE1 (D/UF ) 89 5-20 (a) CTE1 FCBGA.90 5-20 (b) CTE1 FCBGA.90 5-21 (a) / (D/UF ) 91 5-21 (b) / (D/UF ) 91 5-22 FCBGA 92 5-23 / FCBGA 92 5-24 FCBGA 93 VIII
5-25 / FCBGA 93 5-26 (a) (D/UF ) 94 5-26 (b) (D/UF ) 94 5-27 (a) FCBGA 95 5-27 (b) FCBGA 96 5-28 (a) (D/UF ) 97 5-28 (b) (D/UF ) 97 5-29 (a) FCBGA.98 5-29(b) FCBGA 98 5-30 / ( ) 99 5-31 ( ) 99 5-32 ( ) 100 IX
ANSYS E CTE X
Abstract The thesis investigates the thermo-mechanical deformation and stress of a flip-chip package (FCBGA) via both experiment and simulation. First, Shadow Moiré is used to evaluate the warpage of a package at elevated temperature. Then we adopt the finite element method incorporated with the software ANSYS to simulate the warpage of a package and compare the obtained results with experiment at data. Then, the material properties of underfill, the thickness of die and the substrate are considered as important parameters. Their effects on stress and strain fields of package are studied. In case of FCBGA with and without underfill, we find that FCBGA with underfill can reduce stress concentration and increase warpage of a package in comparion with FCBGA without underfill. As for FCBGA with and without heat slug, it is observed that the warpage of FCBGA with heat slug is smaller than that of FCBGA without heat slug. Both stress and strain in the packages of above two cases are similar. The parametric study about the underfill, we find that smaller modulus and CTEs of underfill can reduce the stress and strain of package. However in the consideration of thicknesses of both die and substrate, it is shown that thinner die can reduce stress and strain of package, but thinner substrate does not. So it is suggested that thicknesses of die are the thinner the better. XI
1 1-1 PDA 1958 Jack Kilby (IC)
(Flip-Chip Ball Grid Array, FCBGA) 1-2 ( Packaging ) (IC) (LSI) (Condenser) (Connector) ( ) 1-1 (Level 0) IC Flip Chip (solder Bump) (Level 1) (level 2) (Surface Mount TechnologySMT) (Solder Reflow) 2
(level 3) I/O (Connector) 1-2 (1) (2) (3) (4) IC IC 1-2-1 IC ( Integrated Circuit ) IC 1958 DIP(Dual In-Line Package) (I/O) QFP(Quad Flat Package)SO (Small 3
Outline) PGA(Pin Grid Array) BGA(Ball Grid Array)CSP(Chip Scale Package) 1-3 (Wire Bonding) (Tape-Automated Bonding, TAB) (Flip-Chip) 1-4 (On Side) (Double Side) (Multi-Layer) 1-5 1 (Wire Bonding) 2 (Tape Automated Bonding, TAB) 1960 (GE) IC 3 (Flip Chip) 4
2000 QFP BGA 61.2% 2001 65% BGA 2000 32.3% 2001 40.2%1 CPU GHz CPU Flip ChipIntel FCBGA FCBGA CSP 1-2-2 1960 IBM C4 (Controlled Collapse Chip Connection) 1-6 I/O (Copper pad) IC (Wire Bonding) (Solder) IO (Reflow) (Solder Ball) (Flip Chip Bonder) 5
(Underfill) 2 () () () (Flip Chip Bumping) UBM(Under Bump Metallurgy) 1-7 (Via) (Adhesion Layer) (Diffusion Barrier Layer) (Wetting Layer) TiCr SnPb Al (Intermetallic Compound) CuNi AuAgCuNi UBM 100m~125m () (Flip Chip Assembly) 1-8 6
1-3 FCBGA (Chip Scale Package,CSP) (FCBGA) (Warpage) (Coefficient of Thermal Expansion, CTE) ( CTE 2~3ppm/ CTE 17~20ppm/) 7
(Shadow Moiré) 1-4 1979 Chen Nelson3 (CTE) (Bonded Layer) 1989 Darveaux 4 Kuo5 (Bimetal) 1992 Lau Rice67 (Crack) 1995 Sven Ekkehard8 2000 PaiDing Chou 9 Stiteler Ume10 8
Dang 11 MCM-D Yeh12 Mercado13 PBGA Hwang 14 (Incompatible Mesh)FCBGA (Conventional Mesh) Okura 15 2D E CTE Chiang16 CTE (mismatch) 9
1-5 ANSYS 10
1-1 1-2 11
DIP SIP ZIP (Dual In-Line Package) (Single In-Line Package) (Zig-Zag In-Line Package) QFP PGA SOP (Quad-Flat Package) (Pin Grid Array) (Small Outline Package) 1-3 IC Substrate ( ) (Wire Bonding) Substrate ( ) (Tape Automated Bonding, TAB) Substrate ( ) (Flip Chip) 1-4 12
1-5 1-6C4 13
1-7 UBM 14
Wafer Mount Wafer Saw Flip Chip Bonding Plasma Clean Substrate Baking Flip Chip Reflow Underfill Curing Laser Marking Solder Ball Mount Packaging Flux Clean Solder Ball Reflow Flip Chip Package 1-8 15
16 (Shadow Moir) FCBGA (Warpage) (Underfill) (Shadow Moir) (Shadow Moir ) (Projection Moir) (MoirInterferometry)
2-1 (Grating) CCD 17 w = p tan α + tan β (2-1) w (Out-of plane displacement) p (pitch) (CCD ) 45 17
0 w = p CCD (Phase Shift) 100 lines-per-inch 10mils (1mils=0.001inch) 1~20mil 10mils I( x, y) = B( x, y) + Acos( φ( x, y)) (2-2) (x,y) I(x,y) B(x,y) A φ (x,y) I(x,y) B(x,y)A φ (x,y) 18
19 )), ( cos( ), ( ), ( y x A y x B y x I φ + = + = 2 ), ( cos ), ( ), ( π φ y x A y x B y x I ( ) φ π + = ), ( cos ), ( ), ( y x A y x B y x I + = 2 3 ), ( cos ), ( ), ( π φ y x A y x B y x I (2-3) ) ( ) ( tan ), ( 1 3 2 4 1 I I I I y x = φ (2-4) 100 10mils 0.1mils PS88 1mils~10mils PS88 2-2 CCD 400 300 lines-per-inch 2-3 0.05mils
20 2-4 (UA02UA03 UA04) 2-1 2-5 25 220 25 25100183220 2-6 (Thermal Couple) CCD
3D 2-7 3D y y 21
2-1 Measurement Die (mm) Substrate (mm) Warpage size thickness size thickness Bump (Sn/Pb) Underfill Type Heat Sink X 16x16 0.74 40x40 1.2 63/37 UA02 NA X 16x16 0.74 40x40 1.2 63/37 UA03 NA X 16x16 0.74 40x40 1.2 63/37 UA04 NA X 16x16 0.74 40x40 1.2 63/37 UA02 YES X 16x16 0.74 40x40 1.2 63/37 UA03 YES X 16x16 0.74 40x40 1.2 63/37 UA04 YES X 16x16 0.74 40x40 1.2 63/37 w/o underfill NA 22
a 2-1 CCD 2-2 23
2-3 2-4 24
2-5 2-6 3D 2-7 3D 25
ANSYS (Anand s model) ANSYS ANSYS (Linear Elastic) el { σ } = [ D]{ ε } (3-1) {σ } (stress matrix) [D] (stiffness matrix) { ε el (elastic strain matrix) th } = { ε} { ε } {ε } (total strain matrix) ε ε ε ε ε ε ] [ x y z xy yz zx { ε th } (thermal strain matrix) { th Τ ε } 2D Τ α ] [ y xα Τ = Τ Τ ref Τ Τref 26
α x x xy (Newton-Raphson Method) (1) (3-2) [ K ( u) ]{ u} = { F a } (3-2) [ K( u) ] (Coefficient Matrix) { u} (Vector of Unknown Values) { F a } (Vector of Applied Loads) (2) (3-2) (Residual vector) {R} a r a { R} [ K ]{ u} { F } = { F } { F } { 0} (3-3) { F r } (Vector of Internal Load) (Restoring Force) (3) { R} { u } { } { R} = { R } i + { R} { u} ({ u } { u }) 1 + 2! 2{ R} 2 { u} 2 ({ u } { u }) + L 0 = i i+ 1 i i+ 1 i i i (3-4) 27
i (3-4) T { } = { R } + [ K ]{ ( u }) + O( { u }) 2 (3-5) 0 i i i i T [ Ki ] (Tangent Matrix) { } { u } { } u i = +1 i u i { R} { u} i ({ u }) 2 2 1 { R} 2 i = ({ } { } ) + L { } u 2 i+ 1 u i 2! u O (3-5) i T { 0} = { R } + [ K ]{ ( u }) (3-6) i i (3-2) i ( ) T 1 T 1 a { u } = [ K ] { R } = [ K ] { F } [ K]{ u } i i (3-3) T a [ K ]{ u } = { F } { F r } i i i i i i (3-7) (3-8) { u } = { u +1} { u } (3-9) i T [ K ] i i i i { u } i i { u} i+ 1 i+1 { F a } { F r } i i (4) 28
1. 3-1 u i 2. K T F r K i 3.(3-8) { } i u i i T i { } u i+1 u i+1 u i i 5. i+2 u 2. ~ 4. i+2 3-2 3-3 (5) { } u i < ε u u ref i+1 (3-10) { } R < ε R R ref (3-11) (Vector Norm) { } (3-7) u i a { R} { F } { F r } = i εu ε R (Tolerance) uref R ref (Reference Value) (6) 29
1. { R} = max R 2. L1 { } R 1 3. L2 R = R 1 2 { } = ( R ) 2 2 L1 L2 L2 (ductile material) (brittle material) 3-4 σ = Eε (3-12) 20 (Bump) 30
(Bilinear Kinematic Hardening Plasticity) (Creep) (Anand Model) (Silicon Die) (Substrate) (Bump) (Underfill) (Heat Slug) (Thermal Grease) (Stiffener) (Adhesive) (Solder Mask) (Copper Pad) ANSYS (3-12) 3-4 E (Modulus of Elasticity) (Young's Modulus) E (Tg)Tg Tg E E 31
(Bilinear Kinematic Hardening PlasticityBKIN) (Creep) (Anand Model) Bilinear Kinematic Hardening Plasticity (BKIN) Isotropic hardening rule Kinematic hardening rule 3-5(a)(b) Isotropic hardening rule (a)bc=b CKinematic hardening rule (b) AA =BB 21 von Mises criteria (Distortion Energy Theory) Tresca yield criteria (Maximum Shear Theory) ANSYS Bilinear Kinematic Hardening Plasticity(BKIN) 32
von Mises σ von Mises σ σ = e f ({ σ }) σ e σ e 2 2 2 2 2 [( σ σ ) + ( σ σ ) + ( σ σ ) + 6( τ + τ τ )] 2 1 σ e x y y z z x xy yz + 2 = (3-13) ( σ σ ) x τ τ xy zx τ ( σ σ ) y τ xy yz τ τ ( σ σ ) z zx yz = 0 33 zx (3-14) (3-14) σ (Principal Normal Stress) σ 1 σ 2σ 3 σ e = 1 2 (3-13) (3-15) 2 2 [( σ σ ) + ( σ σ ) + ( σ σ ) ] 2 1 2 2 3 3 1 e (3-15) σ e σ o σ 0 3 = 3-6 Isotropic hardening Kinematic hardening Isotropic hardening 3-7 Kinematic hardening 3-8 Kinematic hardening rule (Bilinear Kinematic Hardening PlasticityBKIN) 22 e
(Creep) ( ) 23 298K63Sn37Pb 456K (Stead State Creep) ANSYS 13 Garofalo & Arrhenius s Law (3-16) ε = C1 2 exp dt d C 4 C T 3 [ sinh ( C σ )] (3-16) ANSYS C 1 C 2 C 3 C 4 Anand Anand s Model Anand241982 34
Anand ( ) Anand Garofalo & Arrhenius s Law (Deformation Resistance) (Constitutive Equation) Garofalo & Arrhenius s Law Anand Anand Garofalo & Arrhenius s Law (3-17) dεeq σ = A sinh ζ dt s 1/ m exp Q KT (3-17) Q activation energym strain-rate sensitivityk Boltzmann s constantmultiplier of stress s deformation resistance s s s s s s a = ho 1 sign 1 εeq (3-18) * * sign a strain rate sensitivityh o hardening constant s ^ * εeq = s exp A Q KT n (3-19) s coefficient of deformation resistance saturation valuen deformation resistance value 35
(3-17)~(3-19) Anand s model Anand s model ANSYS ANSYS 9 Anand 9 3-1 36
3-1 Anand model 37
3-1 i 3-2 i+1 38
3-3 3-4 - 39
s s A B A B A O B C e A O B C e (a) Isotropic Hardening (b) Kinematic Hardening 3-5 Hardening rules 3-6 von Mises 40
3-7 Isotropic Hardening 3-8 Kinematic Hardening 41
ANSYS 4-1 (1) (2) (3) (4) (5) (6) (Popcorn) (7) T(x, t)=t(t) 4-2 4-1 4-2 42
4-3(a)(b) 4-1 E 4-2 BKINCreepAnand 4-34-44-5 2526 27282930 4-4 (4-1)314-5 BKIN 25100183 220 E = 75842 152T (K) (Mpa) (4-1) 150 150 25 100183220 4-6 4-3 ANSYS (Element), ANSYS 43
ANSYSY 4-7 ANSYS ANSYS Newton Raphson Method 4-3-1 ANSYS (Pre-Processing) (Solution) (Post-Processing) 1. 2. 3. (Pre-Processing) 1. BKIN 8 PLANE82 Creep 8 PLANE183 Anand 8 VISCO108 4-8 2 XY 44
2. 3. (mesh) 4-9(a)(b)(c) 14015 17437 20866 (Solution) 1. 2. 2D Ux 0 3. (Step Ramp) (Substep) 45
t t t 4. (1) (Convergence Criteria) ANSYS 0.005 0.05 (2) (Solver) ANSYS PCG(Preconditioned Conjugate Gradient) (3) (Maximum Number of Equilibrium Iterations) ANSYS 15 26 30 (4) (Line Search Option) 1 1 46
ANSYS (5) (Solution Termination Option) (Post-Processing) 4-3-2 (D/UF ) 4-10 47
4-1 Material Properties Young's Modulus (Gpa) Possion's Ratio CTE (ppm/'c) Tg ('C) Die 131 0.28 2.6 n.a. Copper Pad 117 0.344 16.3 n.a. 63Sn37Pb Nonlinear 0.35 24.5 n.a. Substrate 4-2 0.3 15.7 n.a. Solder Mask 2.413 0.45 CTE1=60 CTE2=160 104.2 Heat Slug 117 0.344 16.3 n.a. Stiffener 117 0.344 16.3 n.a. Thermal Grease 40 0.4 232 n.a. Adhesive 1.5 0.35 60 n.a. UA02 4-2 0.35 UA03 4-2 0.35 UA04 4-2 0.35 CTE1=33 CTE2=106 142.3 CTE1=33 CTE2=133 83.5 CTE1=38 CTE2=113 148.3 48
4-2 E Temperature () Substrate (MPa) Underfill UA02 (MPa) Underfill UA03 (MPa) Underfill UA04 (MPa) -50 15865 8733 7168 8638 0 14278 8305 6870 8219 50 13504 7451 6313 7323 100 11895 6279 27.6 6084 150 10499 234.4 0.997 233.3 200 6639 158.6 25.8 109.8 250 3546 184.5 41.8 124.2 4-3 BKIN Temperature (K) Young's modulus (Mpa) Yiled Strength (Mpa) Tangent Modulus (Mpa) 298 29800 24 200 323 27600 20.7 194 348 25400 17.4 189 373 23200 14 184 398 21000 10.8 178 423 18800 7.5 173 448 13960 4.2 168 49
4-4 Creep Creep Constant C1 24800 C2 7.93e-8 C3 3.04 C4 6855.2 4-5 Anand Anand Constant So 12410000 Q/R 9400 A 4000000 Xi 1.5 m 0.303 h o 1378950000 s 13790000 n 0.07 a 1.3 50
(a) (b) (c) 4-1 (a) (b) (c) 51
4-2 11.3mm 0.74mm 8mm 0.5mm 1.2mm 28.3mm (a) 100m 25m 145m (b) 4-3 (a) (b) 52
Young's modulus (GPa) 34 32 30 28 26 24 22 20 18 16 14 12 10 0 20 40 60 80 100 120 140 160 180 Temperature ('C) 4-4 E 4-5 BKIN 53
250 200 Temperature ('C) 150 100 50 0 0 1000 2000 3000 4000 5000 6000 Time (second) 4-6 54
No No 4-7 ANSYS 55
4-8 8 (a) (b) (c) 4-9 (a) (b) (c) 56
4-10 57
58 FCBGA FCBGA (UA02UA03 UA04) 5-1 (a)(b)
25 100183 220 220 183100 25 220 220 UA02 5-2 UA02 3D 5-1 (a)(b) UA02 UA04 UA02 UA04 E Tg CTE UA03 100 100 UA03 Tg UA03 84 E CTE 25~100 UA02 UA03 150 UA04 100 220 UA03 UA02 UA04 32 59
UA02 5-3 (a)(b) UA02 2~3 mils CTE E CTE 5-4 (a)(b)5-5 (a) (b)5-6(a)(b) CTE 16~17ppm/ CTE CTE 60
(Gap) (Inelastic) ANSYS 150-55 5-7 (a)(b)5-8 (a)(b)5-9 (a)(b) measurement BKINCreep Anand UA03 UA02 UA03 150 61
2D 3D ANSYS UA03 150-55 -55 5-10 (a)(b)(c) D/UF 5-11 D/UF 62
63 5-12 (a)(b) 5-13(a)(b) 32 FCBGA IC ANSYS (UA03) CTE
(Die/Substrate) UA03 0.25 0.5 2 4 5-14 (a)(b) D/UF 5-16 5-18 5-15 5-17 E E 5-15~5-18 E 0.25 0.5 1 2 4 5-1 E D/UF E D/UF E E D/UF E D/UF 64
CTE UA03 CTE1 CTE1 33ppm/ 0.25 0.5 2 8ppm/16ppm/ 66ppm/ 5-19 (a)(b) CTE1 D/UF CTE1 5-20 (a)(b) 5-2 CTE1 Tg CTE1 CTE1 0.5 0.25 0.5 0.25 5-21 (a)(b) / D/UF 5-23 5-25 / 65
5-22 5-24 5-21 (a)(b) 5-3 1~2MPa 1/8 1/16 1/4 5-26 (a)(b) D/UF 5-27 (a)(b) 5-26 (a)(b) 5-4 1/4 1/4 5-28 (a)(b) 66
0.62(0185mm/0.3mm) 0.62(0.74mm/1.2mm) 5-29 (a)(b) 5-5 0.62(0185mm/0.3mm) 0.185mm 0.185mm/0.3mm 0.185mm/1.2mm 5-303132 300MPa 33-55 E CTE1 5-6 5-7 E CTE1 CTE1 E 5-85-9 5-10 67
1 E E E CTE CTE E CTE 68
5-1 E D/UF D/UF E (Mpa) (Mpa) (Mpa) 0.25xE -18.6 50.4 42.4 0.06 0.5xE -32.4 94.3 43.6 0.068 E (Ref.) -88.1 175 44.3 0.073 2xE -171 319 44.2 0.072 4xE -260 558 43.7 0.08 5-2 CTE1 D/UF D/UF CTE1 (Mpa) (Mpa) (Mpa) 0.25xCTE1-58.6 134 42.5 0.06 0.5CTE1-68 147 43.1 0.064 CTE1(Ref.) -88.1 175 44.3 0.073 2xCTE1-127 230 46.8 0.09 69
5-3 / / D/UF D/UF (mm/mm) (Mpa) (Mpa) (Mpa) 0.15 (0.185/1.2) -51.1 152 42.3 0.059 0.31 (0.37/1.2) 0.62 (Ref.) (0.74/1.2) 1.23 (0.74/0.6) 2.46 (0.74/0.3) -64.2 154 42.7 0.061-88.1 175 44.3 0.073-87 177 43.6 0.068-86.8 174 42.6 0.061 5-4 / D/UF D/UF (mm/mm) (Mpa) (Mpa) (Mpa) 0.04 (0.046/1.2) -17.8 139 42.5 0.06 0.08 (0.093/1.2) 0.15 (0.185/1.2) 0.31 (0.37/1.2) 0.62 (Ref.) (0.74/1.2) -45.5 147 42.4 0.059-51.1 152 42.3 0.059-64.2 154 42.7 0.061-88.1 175 44.3 0.073 70
5-5 / D/UF D/UF (mm/mm) (Mpa) (Mpa) (Mpa) 0.15 (0.185/1.2) -51.1 152 42.3 0.059 0.62 (0.185/0.3) 0.62 (Ref.) (0.74/1.2) 2.46 (0.74/0.3) -45.3 146 40.8 0.054-88.1 175 44.3 0.073-86.8 174 42.6 0.061 5-6 E 0.25xE 0.5xE E 2xE 4xE 5.93 5.99 6.06 6.18 6.35 18.79 18.77 18.59 18.41 18.43 5-7 CTE1 0.25xCTE1 0.5xCTE1 CTE1 2xCTE1 6.04 6.05 6.06 6.09 19.37 19.12 18.59 17.56 71
5-8 / 0.15 (0.185mm/1.2mm) 0.31 (0.37mm/1.2mm) 0.62 (0.74mm/1.2mm) 1.23 (0.74mm/0.6mm) 2.47 (0.74mm/0.3mm) 7.44 7.56 6.06 6.74 5.63 25.38 25.46 18.59 11.38-40.46 5-9 0.04 (0.046mm/1.2mm) 0.08 (0.093mm/1.2mm) 0.15 (0.185mm/1.2mm) 0.31 (0.37mm/1.2mm) 0.62 (0.74mm/1.2mm) 4.47 6.42 7.44 7.56 6.06 14.12 21.57 25.38 25.46 18.59 5-10 0.15 (0.185mm/1.2mm) 0.62 (0.74mm/1.2mm) 0.62 (0.185mm/0.3mm) 2.47 (0.74mm/0.3mm) 7.44 6.06 22.36 5.63 25.38 18.59 43.42-40.46 72
Warpage - Full Area (mils) 10 8 6 4 2 0-2 -4-6 0 50 100 150 200 250 Temperature ('C) UA02 UA03 UA04 5-1 (a) Warpage - Die Area (mils) 5 4 3 2 1 0-1 -2 UA02 UA03 UA04-3 0 50 100 150 200 250 Temperature ('C) 5-1 (b) 73
25 100 183 220 D183 D100 D25 5-2 UA02 3D 74
Warpage - Full Area (mils) 9 8 7 6 5 4 3 2 1 0-1 -2-3 -4-5 -6 w/o UF UA02 0 50 100 150 200 250 Temperature ('C) 5-3 (a) Warpage - Die Area (mils) 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0-0.5-1.0-1.5-2.0-2.5-3.0 0 50 100 150 200 250 Temperature ('C) w/o UF UA02 5-3 (b) 75
Warpage - Full Area (mils) 8 6 4 2 0-2 -4-6 UA02 w/o HS UA02 with HS 0 50 100 150 200 250 Temperature ('C) 5-4 (a) UA02 5 Warpage - Die Area (mils) 4 3 2 1 0-1 -2 UA02 w/o HS UA02 with HS -3 0 50 100 150 200 250 Temperature ('C) 5-4 (b) UA02 76
6 Warpage -Full Area (mils) 4 2 0-2 -4 UA03 w/o HS UA03 with HS 0 50 100 150 200 250 Temperature ('C) 5-5 (a) UA03 3 Warpage -Die Area (mils) 2 1 0-1 -2 UA03 w/o HS UA03 with HS 0 50 100 150 200 250 Temperature ('C) 5-5 (b) UA03 77
10 Warpage -Full Area (mils) 8 6 4 2 0-2 -4 0 50 100 150 200 250 Temperature ('C) UA04 w/o HS UA04 with HS 5-6 (a) UA04 5 Warpage - Die Area (mils) 4 3 2 1 0-1 -2 UA04 w/o HS UA04 with HS -3 0 50 100 150 200 250 Temperature ('C) 5-6 (b) UA04 78
Warpage - Full Area (mils) 12 10 8 6 4 2 0-2 -4-6 0 50 100 150 200 250 Temperature ('C) Measurement BKIN Creep Anand 5-7 (a) UA02 Warpage - Die Area (mils) 4 3 2 1 0-1 -2 Measurement BKIN Creep Anand -3 0 50 100 150 200 250 Temperature ('C) 5-7 (b) UA02 79
Warpage - Full Area (mils) 10 8 6 4 2 0-2 -4-6 0 50 100 150 200 250 Temperature ('C) measurement BKIN Creep Anand 5-8 (a) UA03 4 Warpage - Die Area (mils) 3 2 1 0-1 -2 measurement BKIN Creep Anand 0 50 100 150 200 250 Temperature ('C) 5-8 (b) UA03 80
Warpage - Full Area (mils) 12 10 8 6 4 2 0-2 -4-6 0 50 100 150 200 250 Temperature ('C) measurement BKIN Creep Anand 5-9 (a) UA04 5 Warpage -Die Area (mils) 4 3 2 1 0-1 -2 measurement BKIN Creep Anand -3 0 50 100 150 200 250 Temperature ('C) 5-9 (b) UA04 81
Normal Stress (MPa) 50 40 30 20 10 0-10 -20-30 -40-50 -60-70 -80-90 -100 w/o UF with UF 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-10 (a) (D/UF 200 150 w/o UF with UF Shear Stress (MPa) 100 50 0-50 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-10 (b) (D/UF 82
105 100 w/o UF with UF Principal Stress (MPa) 95 90 85 80 75 70 0 2 4 6 8 10 12 Dist from die center to die edge (mm) 5-10 (c) ( with UF without UF 5-11 FCBGA 83
40 20 w/o HS with HS Normal Stress (MPa) 0-20 -40-60 -80-100 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-12 (a) (D/UF 200 150 w/o HS with HS Shear Stress (MPa) 100 50 0-50 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-12 (b) (D/UF 84
without HS with HS 5-13 (a) FCBGA without HS with HS 5-13 (b) FCBGA 85
Normal Stress (MPa) 300 200 100 0-100 -200 0.25xE 0.5xE E(Ref.) 2xE 4xE -300 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-14 (a) E (D/UF Shear Stress (MPa) 600 550 500 450 400 350 300 250 200 150 100 50 0-50 -100-150 -200-250 -300 0.25xE 0.5xE E(Ref.) 2xE 4xE 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-14 (b) E (D/UF 86
Reference (E, Tg, CTE1) 5-15 FCBGA 0.25xE 0.5xE 2xE 4xE 5-16 E FCBGA 87
Reference (E, Tg, CTE1) 5-17 FCBGA 0.25xE 0.5xE 2xE 4xE 5-18 E FCBGA 88
Normal stress (MPa) 40 20 0-20 -40-60 -80-100 0.25xCTE 0.5xCTE CTE(Ref.) 2xCTE -120-140 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-19 (a) CTE1 (D/UF Shear Stress (MPa) 260 240 220 200 180 160 140 120 100 80 60 40 20 0-20 -40-60 -80-100 0.25xCTE 0.5xCTE CTE(Ref.) 2xCTE 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-19 (b) CTE1 (D/UF 89
0.25xCTE1 0.5xCTE1 2xCTE1 5-20 (a) CTE1 FCBGA 0.25xCTE1 0.5xCTE1 2xCTE1 5-20 (b) CTE1 FCBGA 90
Normal Stress (MPa) 20 0-20 -40-60 -80 Ratio=2.47 (0.74mm/0.6mm) Ratio=1.23 (0.74mm/0.3mm) Ratio=0.62 (0.74mm/1.2mm) Ratio=0.31 (0.37mm/1.2mm) Ratio=0.15 (0.185mm/1.2mm) -100 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-21 (a) / (D/UF Shear Stress (MPa) 200 150 100 50 0 Ratio=2.47 (0.74mm/0.6mm) Ratio=1.23 (0.74mm/0.3mm) Ratio=0.62 (0.74mm/1.2mm) Ratio=0.31 (0.37mm/1.2mm) Ratio=0.15 (0.185mm/1.2mm) -50-0.05 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge of (mm) 5-21 (b) / (D/UF 91
Reference (0.74mm/1.2mm) 5-22 FCBGA 0.185mm/1.2mm 0.37mm/1.2mm 0.74mm/0.6mm 0.74mm/0.3mm 5-23 FCBGA 92
Reference (0.74mm/1.2mm) 5-24 FCBGA 0.185mm/1.2mm 0.37mm/1.2mm 0.74mm/0.6mm 0.74mm/0.3mm 5-25 FCBGA 93
Normal Stress (MPa) 40 30 20 10 0-10 -20-30 -40-50 -60-70 -80-90 -100 Ratio=0.04 (0.046mm/1.2mm) Ratio=0.08 (0.093mm/1.2mm) Ratio=0.15 (0.185mm/1.2mm) Ratio=0.31 (0.37mm/1.2mm) Ratio=0.62 (0.74mm/1.2mm) 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-26 (a) (D/UF Shear Stress (MPa) 200 180 160 140 120 100 80 60 40 20 0-20 -40-60 Ratio=0.04 (0.046mm/1.2mm) Ratio=0.08 (0.093mm/1.2mm) Ratio=0.15 (0.185mm/1.2mm) Ratio=0.31 (0.37mm/1.2mm) Ratio=0.62 (0.74mm/1.2mm) 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-26 (b) (D/UF 94
0.046mm/1.2mm 0.093mm/1.2mm 0.185mm/1.2mm 0.37mm/1.2mm 0.74mm/1.2mm 5-27 (a) FCBGA 95
0.046mm/1.2mm 0.093mm/1.2mm 0.185mm/1.2mm 0.37mm/1.2mm 0.74mm/1.2mm 5-27 (b) FCBGA 96
40 20 Ratio=0.15 (0.185mm/1.2mm) Ratio=0.62 (0.74mm/1.2mm) Ratio=0.62 (0.185mm/0.3mm) Ratio=2.47 (0.74mm/0.3mm) Normal Stress (MPa) 0-20 -40-60 -80-100 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-28 (a) (D/UF Shear Stress (MPa) 200 150 100 50 0 Ratio=0.15 (0.185mm/1.2mm) Ratio=0.62 (0.74mm/1.2mm) Ratio=0.62 (0.185mm/0.3mm) Ratio=2.47 (0.74mm/0.3mm) -50 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 Dist from bump edge to die edge (mm) 5-28 (b) (D/UF 97
5-29 (a) FCBGA 5-29 (b) FCBGA 98
Princinpal stress (MPa) 170 160 150 140 130 120 110 100 90 80 70 60 50 40 30 Ratio=0.62 (0.74mm/1.2mm) Ratio=1.23 (0.74mm/0.6mm) Ratio=2.47 (0.74mm/0.3mm) Ratio=0.31 (0.37mm/1.2mm) Ratio=0.15 (0.185mm/1.2mm) 0 2 4 6 8 10 12 Dist from die center to die edge (mm) 5-30 / ( Principal Stress (MPa) 160 140 120 100 80 60 40 Ratio=0.15 (0.185mm/1.2mm) Ratio=0.62 (0.74mm/1.2mm) Ratio=0.62 (0.185mm/0.3mm) Ratio=2.47 (0.74mm/0.3mm) 0 2 4 6 8 10 12 Dist from die center to die edge (mm) 5-31 ( 99
Principal Stress (MPa) 180 160 140 120 100 80 60 40 20 0-20 Ratio=0.04 (0.046mm/1.2mm) Ratio=0.08 (0.093mm/1.2mm) Ratio=0.15 (0.185mm/1.2mm) Ratio=0.31 (0.37mm/1.2mm) Ratio=0.62 (0.74mm/1.2mm) 0 2 4 6 8 10 12 Dist from die center to die edge (mm) 5-32 ( 100
ANSYS 6-1 1. 2. 3. E Tg CTE 4. 5. 101
6-2 1. CTE 2. 3. 5000 3D 3D 2D 4. 102
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