Packaging with double-side cooling capability for SiC devices, based - PowerPoint PPT Presentation

Packaging with double-side cooling capability for SiC devices, based on silver sintering IECON 2018 Cyril B UTTAY 1 , Raphaël R IVA 1 , Bruno A LLARD 1 ,Marie-Laure L OCATELLI 2 , Vincent B LEY 2 1 Laboratoire Ampère, Lyon, France 2 Laboratoire LAPLACE, Toulouse, France 21/10/18 1 / 16

Outline Introduction Manufacturing of the 3-D structure Results Conclusion 2 / 16

Outline Introduction Manufacturing of the 3-D structure Results Conclusion 3 / 16

Double Side Cooling ◮ SiC JFETs (or MOSFETs) sensitive to thermal run-away ➜ Need for efficient cooling, despite high temperature capability ◮ Standard packaging offers cooling through one side of the die only ◮ “Sandwich” package performs thermal management on both sides ◮ Requires special features for topside contact 4 / 16

Double Side Cooling ◮ SiC JFETs (or MOSFETs) sensitive to thermal run-away ➜ Need for efficient cooling, despite high temperature capability ◮ Standard packaging offers cooling through one side of the die only ◮ “Sandwich” package performs thermal management on both sides ◮ Requires special features for topside contact 4 / 16

Double Side Cooling ◮ SiC JFETs (or MOSFETs) sensitive to thermal run-away ➜ Need for efficient cooling, despite high temperature capability ◮ Standard packaging offers cooling through one side of the die only ◮ “Sandwich” package performs thermal management on both sides ◮ Requires special features for topside contact 4 / 16

Outline Introduction Manufacturing of the 3-D structure Results Conclusion 5 / 16

The proposed 3-D Structure V bus J H OUT J L 0,15 mm 0,15 mm 0,3 mm 0,3 mm J L J H GND ◮ Two ceramic substrates, in “sandwich” configuration ◮ Two SiC JFET dies (SiCED) ◮ Assembled using silver sintering ◮ 25.4 mm × 25.4 mm (1 in × 1 in) 6 / 16

Ceramic Substrates Scale drawing for 2.4 × 2.4 mm 2 die Copper Alumina 0.16 mm 0.15 mm 0,15 mm Source Gate Source 0,3 mm 0.2 mm SiC JFET 0.3 mm Drain ◮ Etching accuracy exceeds standard design rules ◮ Double-step copper etching for die contact ➜ Custom etching technique 7 / 16

Preparation of the Substrates plain DBC board ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates plain DBC board 1a - Photosensitive resin coating ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates plain DBC board 1a - Photosensitive resin 1b - Exposure and coating Development ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates plain DBC board 1a - Photosensitive resin 1b - Exposure and 2 - Etching coating Development ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates plain DBC board 1a - Photosensitive resin 1b - Exposure and 2 - Etching coating Development ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates plain DBC board 1a - Photosensitive resin 1b - Exposure and 2 - Etching 3a - resin coating coating Development ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates plain DBC board 1a - Photosensitive resin 1b - Exposure and 2 - Etching 3a - resin coating coating Development 3b - Exposure and Developpment ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates plain DBC board 1a - Photosensitive resin 1b - Exposure and 2 - Etching 3a - resin coating coating Development 4a - Photosentive fi lm 3b - Exposure and laminating Developpment ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates plain DBC board 1a - Photosensitive resin 1b - Exposure and 2 - Etching 3a - resin coating coating Development 4b - Exposure and 4a - Photosentive fi lm 3b - Exposure and Development laminating Developpment ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates plain DBC board 1a - Photosensitive resin 1b - Exposure and 2 - Etching 3a - resin coating coating Development 5 - Etching 4b - Exposure and 4a - Photosentive fi lm 3b - Exposure and Development laminating Developpment ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates plain DBC board 1a - Photosensitive resin 1b - Exposure and 2 - Etching 3a - resin coating coating Development 6 - Singulating 5 - Etching 4b - Exposure and 4a - Photosentive fi lm 3b - Exposure and Development laminating Developpment ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Preparation of the Substrates ◮ Final patterns within 50 µ m of desired size ◮ Two designs, for 2.4 mm and 4 mm dies ◮ Die top metallized (PVD) with Ti/Ag ◮ Total copper thickness 300 µ m, ≈ 150 µ m per step 8 / 16

Bonding Material: Silver Sintering Silver Paste ◮ Based on micro-scale silver particles (Heraeus LTS-117O2P2) ◮ Low temperature (240 ° C) sintering Göbl, C. et al “Low temperature sinter technology Die attachment for automotive ◮ Low pressure (2 MPa) process power electronic applications” proc of APE, 2006 No liquid phase involved: ◮ No movement of the die ◮ No bridging across terminals ◮ No height compensation thanks to wetting 9 / 16

Assembly Screen printing ◮ Ceramic jigs for alignment of dies and substrate ◮ Pre-drying of paste to prevent smearing ◮ Two sintering steps using the same temperature profile 10 / 16

Assembly Screen printing 2- Mounting in alignment jig ◮ Ceramic jigs for alignment of dies and substrate ◮ Pre-drying of paste to prevent smearing ◮ Two sintering steps using the same temperature profile 10 / 16

Assembly Screen printing 2- Mounting in 3- Die-alignment jig, alignment jig dies and spacer placing ◮ Ceramic jigs for alignment of dies and substrate ◮ Pre-drying of paste to prevent smearing ◮ Two sintering steps using the same temperature profile 10 / 16

Assembly Screen printing 2- Mounting in 3- Die-alignment jig, 4 - First sintering step alignment jig dies and spacer placing ◮ Ceramic jigs for alignment of dies and substrate ◮ Pre-drying of paste to prevent smearing ◮ Two sintering steps using the same temperature profile 10 / 16

Assembly Screen printing 2- Mounting in 3- Die-alignment jig, 4 - First sintering step 5 - Removal of die- alignment jig dies and spacer placing alignment jig ◮ Ceramic jigs for alignment of dies and substrate ◮ Pre-drying of paste to prevent smearing ◮ Two sintering steps using the same temperature profile 10 / 16

Assembly Screen printing 2- Mounting in 3- Die-alignment jig, 4 - First sintering step 5 - Removal of die- alignment jig dies and spacer placing alignment jig 6 - Screen printing on "drain" substrate ◮ Ceramic jigs for alignment of dies and substrate ◮ Pre-drying of paste to prevent smearing ◮ Two sintering steps using the same temperature profile 10 / 16

Assembly Screen printing 2- Mounting in 3- Die-alignment jig, 4 - First sintering step 5 - Removal of die- alignment jig dies and spacer placing alignment jig 6 - Screen printing on 7 - Mounting in "drain" substrate alignment jig ◮ Ceramic jigs for alignment of dies and substrate ◮ Pre-drying of paste to prevent smearing ◮ Two sintering steps using the same temperature profile 10 / 16

Assembly Screen printing 2- Mounting in 3- Die-alignment jig, 4 - First sintering step 5 - Removal of die- alignment jig dies and spacer placing alignment jig 6 - Screen printing on 8 - Second sintering step 7 - Mounting in "drain" substrate alignment jig ◮ Ceramic jigs for alignment of dies and substrate ◮ Pre-drying of paste to prevent smearing ◮ Two sintering steps using the same temperature profile 10 / 16