Process Solutions for TSV-Based 3D IC Integration
SAMCO Inc. > Markets > Process Solutions for TSV-Based 3D IC Integration
1. Via Hole Fabrication using the Bosch Process
Precise tilt control is critical in the silicon via hole fabrication because tilt angle of just 1° could result in the misalignment of a 200 μm thick TSV by as much as 2 μm. An absolutely vertical via hole etching can be achieved with uniform plasma discharge. Tilt angle and etch depth are highly stable in consecutive run of 25 wafers. Furthermore, sidewall smoothing process will reduce scallop size on sidewalls and prevent delamination of Cu plug.
2. Photoresist Ashing
Samco RIE systems with double atmospheric cassettes minimize downtime for wafer transfer and improve throughput of photoresist plasma ashing process.
3. Insulation Film Deposition on Via Hole
A TEOS-Oxide film with excellent step coverage was deposited using Samco’s unique Cathode PECVD technology.
Another process feature of our plasma CVD technologies is low-temperature deposition. There are high demands in advanced packaging research communities for low-temperature processes due to the use of temperature-sensitive adhesives which are used for temporary wafer bonding of thinned wafers. Samco offers low-temperature PECVD process solutions (including under 80°C) of SiO2 and SiNx deposition to meet such demands. SiO2 deposited at 120°C or 150°C showed low leakage (~ nA) between silicon substrate and passivation with 100 μm deep via.
4. Exposure of Lower Electrode by SiO2 Etching
A SiO2 film on via hole bottom was successfully removed by RIE process.
5. Barrier Layer Formation
6. Cu Electroplating
7. CMP
8. Cu Plug Exposure by Dry Etching
Symmetrical evacuation and optimized gas manifold design of RIE systems enable high-uniformity etching over the sample stage.
9. SiO2 Passivation Film Deposition by PECVD
Film stress of SiO2 passivation is highly controllable using Cathode PECVD technology. By adjusting process time of compressive layers and tensile layers, the film stress is stable even 24 hours after the deposition.
10. Cu Plug Exposure by SiO2 Plasma Etching
Double Cassettes and multi-joint robot wafer handling of Samco’s atmospheric cassette RIE systems improve throughput of SiO2 etching.
11. Photoresist Plasma Ashing
Samco offers multiple systems and technologies to meet customers’ demands for photoresist plasma ashing process.
