1.Alternative solution to 2.5D
2. Substrate for Chiplets*:
RDL 1: 0.5 µm Dielectric 1: SiO2, SiNx
RDL 2: 2 ~ 10µm Dielectric 2: Polyimide
RDL 3: 15~50µm Dielectric 3: Laminate Materials
*: Proposed by DC Hu in
“An Innovative System Intergration Technology beyond BEOL”
DC Hu, IEEE International Interconnection Technology conference, June 2018
Cost Savings in eHDF Structure Saving 1: No Core in Interposer and Substrate
- Save silicon and Substrate core materials cost.
- Save TSV and TLV via forming and via filling process cost.
Cost Savings in eHDF Structure Saving 2: No Solder between the Interposer and Substrate
- Cost saving on surface finishing, Solder mask, solders and underfill material.
- No interposer to substrate assembly process cost.
- Less materials used and environmentally friendly solution.
Compare 2.5D and eHDF Solution
Z Height Comparison
- Thickness reduction
- No intra-solder reliability issues.
Chips on eHDF Substrate
- No Silicon(TSV) and laminated cores.
- Need only half of the the interposer and substrate surface finishing.
- No need of solders between the Interposer and the substrate.
- No interposer to substrate assembly cost.
- Better electrical performance and simplify the logistic.
Compare HPC Substrate Solutions in the Market
✤: Can be mechanically enhanced by eHDF-OCS or eHDF-eST structure.
eHDF Technology Passed the Substrate Companies Reliability Evaluation
eHDF-OCS and eHDF-eST substrate have passed the substrate company reliability evaluation, respectively.
eHDF structure on Cored Substrate
eHDF structure with embedded Stiffener
*: Picture Curtesy of Nanya PCB.