AMB Silicon Nitride (Si₃N₄) Substrate for Automotive Traction Inverters and DC/DC Converters

AMB Silicon Nitride Substrate Applications

• Silicon Nitride AMB Substrate for EV Inverter

  ✅Key Advantages

  1. Lower Junction Temperature Rise – Silicon Nitride AMB Substrate for EV Inverter reduces Rth(j-c) by ~15% when using 500 µm copper compared to standard AlN DBC in SiC traction modules.
  2. Extended Power Cycling Life – With AMB Si₃N₄ Ceramic Substrate for Power Module structure, SiC devices maintain >10,000 cycles (−40 to 150 °C) without copper delamination or substrate cracking.
  3. Low Contact Resistance Drift – Copper bonded to the AMB Si₃N₄ substrate maintains <0.1 mΩ resistance shift after 100 hours at 175 °C, ensuring long-term inverter efficiency.

  ✅ Problem Solved

  A European EV inverter manufacturer experienced die-attach fatigue and DBC substrate fracture at around 4,000 thermal cycles. After replacing Al₂O₃ DBC with Silicon Nitride AMB Substrate for EV Inverter (0.38 mm Si₃N₄ + 300 µm copper), module life increased to over 9,500 cycles, case temperature dropped by 7 °C at 600 A continuous current, and warranty failure rate decreased from 0.45% to 0.08%.

• AMB Si₃N₄ Ceramic Substrate for Power Module in PV

  ✅Key Advantages

  1. Continuous Output Stability – AMB Si₃N₄ Ceramic Substrate for Power Module lowers thermal resistance by 0.12 K/W, enabling inverter operation at full load without derating.
  2. High Voltage Reliability – Dielectric strength above 20 kV/mm ensures safety in 1500 V DC bus environments.
  3. Higher Sintering Yield – Warpage below 25 µm per panel allows <2% void rate in Ag-sintered IGBT dies, improving bonding reliability.

  ✅ Problem Solved

  A solar inverter company reported module shutdowns caused by IGBT overheating above 120 °C during peak generation. After switching to AMB Si₃N₄ Ceramic Substrate for Power Module, junction temperature dropped by 9–11 °C, thermal trip events were reduced by 75%, and system uptime increased from 97.2% to 99.1% in a 50 MW installation.

• AMB Si₃N₄ Substrate for Power Module in Rail Traction & Industrial Drives

  ✅Key Advantages

  1. Shock and Vibration Endurance – AMB Si₃N₄ Ceramic Substrate for Power Module withstands >20 g impact without micro-cracking in railway converters.
  2. Reduced Maintenance Cost – Improved fracture toughness and copper adhesion extend the traction module lifetime to over 5 years, doubling maintenance intervals.
  3. High Current Overload Capability – 500 µm copper AMB structure handles temporary overloads above 900 A without warpage or solder lift-off.

  ✅ Problem Solved

  A traction system integrator observed cracks in AlN-based substrates after 18 months of metro operation. After adopting AMB Si₃N₄ Ceramic Substrate for Power Module, module service life exceeded 5 years, unplanned maintenance frequency dropped by 40%, and annual shutdown-related costs were significantly reduced.

AMB Silicon Nitride Substrate Usage Instructions

• Installation & Assembly

  1. Clean copper and ceramic surfaces using ethanol, isopropanol, or plasma cleaning to remove oils and oxide layers before silver sintering or soldering.
  2. For silver sintering, apply uniform pressure of 20–40 MPa across the whole panel to avoid voids under SiC chips.
  3. During soldering, heat the entire substrate gradually to prevent thermal gradient; localized heating above 300 °C for more than 10 minutes may cause copper lifting or ceramic stress cracks.
  4. Use alignment pins or positioning holes to keep chip placement deviation within ±0.05 mm.

• Storage

  1. Store in a dry room with humidity <50% RH and temperature 20–25 °C to avoid copper surface oxidation and moisture absorption by the ceramic.
  2. Keep the substrate in vacuum-sealed moisture barrier bags with desiccant until assembly to prevent surface oxidation or warping.
  3. Once opened, use within 48 hours or reseal in nitrogen-filled packaging.

• Cleaning & Maintenance

  1. Recommended cleaning: ethanol or ultrasonic cleaning in deionized water with neutral detergent (<pH 8).
  2. Avoid solutions containing fluoride, alkali, or ammonia, which may attack the copper layer or weaken metallization.
  3. Avoid bending, vibration impact, or clamping directly on the ceramic edge to prevent micro-cracks.
  4. If surface oxidation occurs before bonding, use plasma or micro sandblasting followed by vacuum drying.

• Common Mistakes & Solutions

  Issue	Cause	Solution
  Silver paste voids during bonding	Copper or ceramic surface oxidation/moisture	Plasma cleaning + 120 °C vacuum drying for 30 min before bonding
  Copper delamination or peeling	Local overheating (>850 °C) or rapid cooling	Control the heating rate <5 °C/s and avoid torch heating
  Warpage after sintering	Uneven pressure during silver sintering or insufficient fixturing	Use graphite fixtures, weight blocks or flat tooling plates
  Solder joint cracking	Temperature cycling and CTE mismatch stress	Use Ag-sintering or Ni/Au finish instead of SnPb solder
  Scratches on the copper surface	Improper handling or stacking without separators	Use soft polymer sheets between each piece during transport

 High Thermal Conductivity AMB Silicon Nitride Substrate FAQ

1. Q: What is a Si3N4 active metal brazed substrate, and how is it different from DBC alumina or AlN substrates?
   A: A Si3N4 active metal brazed substrate uses a silicon nitride ceramic core bonded with copper using Ti-bearing brazing alloy. Unlike Al₂O₃ or AlN DBC, the active metal brazing silicon nitride substrate offers fracture toughness of 6–8 MPa·m¹ᐟ² and survives over 10,000 power cycles, making it suitable for SiC power devices.
2. Q: Why do EV traction inverter manufacturers choose silicon nitride substrate AMB copper clad instead of AlN or ceramic PCB?
   A: Because the silicon nitride substrate AMB copper clad combines high mechanical strength and copper layer thickness up to 500 µm, resulting in 15–20% lower thermal resistance and reduced substrate cracking during vibration, which is critical in automotive inverter environments.
3. Q: What is the typical thickness tolerance and flatness of the active metal brazing silicon nitride substrate?
   A: Si₃N₄ AMB panels can be controlled to ±0.03–0.05 mm in thickness, and flatness can be maintained under 20–30 µm per 140×190 mm panel, which is necessary for pressure sintering and high-area SiC die attachment.
4. Q: What copper thickness options are available for silicon nitride substrate AMB copper clad boards?
   A: Common configurations include 70 µm, 140 µm, 300 µm, and 500 µm copper on one or both sides. Thicker copper helps reduce current density and heat flux but requires precise warpage control from a qualified Si₃N₄ AMB substrate manufacturer.
5. Q: Can AMB Si3N4 substrates be used for silver sintering of SiC MOSFETs and IGBTs?
   A: Yes. The low warpage of active metal brazed silicon nitride substrates ensures uniform pressure and void-free sintered layers, with <2% porosity when pressure is applied at 20–40 MPa.
6. Q: Can a Si3N4 active metal brazed substrate support double-sided cooling designs in power modules?
   A: Yes. Because the ceramic layer has CTE close to SiC chips and high flexural strength (>800 MPa), it allows double-sided copper structures for baseplate-free modules and liquid-cooled SiC automotive inverters.
7. Q: What information should I provide to a Si₃N₄ AMB substrate manufacturer for custom production?
   A: You should specify ceramic thickness, copper thickness, panel or unit size, copper trace layout (Gerber or DXF file), surface finish (Ag, Ni, Ni-Au), warpage tolerance, and bonding method (soldering or silver sintering).

Active Metal Brazing Silicon Nitride Substrate Reviews

• ⭐️⭐️⭐️⭐️
  We switched to a silicon nitride substrate AMB copper clad for our 750 V SiC inverter project. After 9,800 power cycles, none of the modules showed copper lift-off or ceramic cracks. The Si₃N₄ active metal brazed substrate clearly improved thermal stability by about 8 °C compared with AlN DBC.
  -- Markus Hoffmann, R&D Engineer, E-Traction Systems GmbH
• ⭐️⭐️⭐️⭐️⭐️
  We ordered custom AMB panels from ADCERAX, which is a Si₃N₄ AMB substrate manufacturer in China for our EV traction inverters. They followed our copper layout and thickness requirements (0.32 mm ceramic + 300 µm Cu), and the warpage stayed under 25 µm, which was critical for silver sintering of SiC dies.
  -- Kazuki Tanaka, Power Electronics Manager, Kyoto Drives Corp.
• ⭐️⭐️⭐️⭐️⭐️
  Our previous DBC boards had solder fatigue issues in high-load UPS systems. After using active metal brazing on a silicon nitride substrate, the junction temperature dropped from 118 °C to 107 °C under full load, and thermal trip alarms reduced by nearly 70%.
  -- Sarah Mitchell, Procurement Lead, VoltSecure Power Solutions
• ⭐️⭐️⭐️⭐️⭐️
  As a small OEM company, we needed a low-volume customized Si₃N₄ active metal brazed substrate with 500 µm copper for high-current rectifiers. ADCERAX accepted 30-piece prototyping, provided Gerber feedback within 48 hours, and delivered panels with no copper oxidation or edge chipping.
  -- Giovanni Russo, Technical Director, ModuTech Engineering S.r.l.