High-Density 3D Integrated Silicon Capacitors

October 29, 2015 by Jeff Shepard

Two years after the launch of the Passive Integated Connective Substrate (PICS) project (funded by the FP7 funding instrument dedicated to research for the benefit of SMEs), three European SMEs, IPDiA, Picosun and SENTECH Instruments along with CEA-Leti and Fraunhofer IPMS-CNT announce the major technological results achieved during this program. Started in September 2013, the PICS project was focused on developing innovative dielectric materials deposited by atomic layer deposition (ALD) and related tools (ALD batch tool and etching tool) to bring to mass production a new technology of high- density and high-voltage 3D trench capacitors targeting high-end markets like medical or aeronautics.

Capacitors are key components presented in every electronic module. The integrated silicon capacitors technology offered by the SME IPDiA outperforms current technologies (using ceramic or tantalum substrates) in stability in temperature, voltage, aging and reliability and enables to build highly-integrated and high-performance electronic modules.

The consortium’s three major technological results are: 1) A novel ALD batch tool was developed by Picosun and Fraunhofer IPMS-CNT. It enables to reduce cost-of-ownership and deliver better uniformity and step coverage for high-K dielectrics into 3D structures. With its demonstrated, optimized and production-proven ALD processes, Picosun is solidifying its position as a technological leader in the IC, Semiconductor, MEMS markets, from R&D to production systems.

2) A new process for accurately etching high-K dielectrics, which are very specific materials, was demonstrated by SENTECH with the help of Fraunhofer IPMS-CNT. As a result, SENTECH has the potential to gain market share in the field of high-k materials, which have high interest for different applications, e.g. LED, MEMS, magnetic data storage.

3) Two new dielectric stacks were developed and integrated into the IPDiA 3D trench capacitors by IPDiA, CEA-Leti and Fraunhofer IPMS-CNT. The initial specifications were fulfilled and proven by electrical measurements. A new record on capacitance density (>500nF/mm² at 3.3V) and an extended operation voltage (10V with 150nF/mm²) were obtained, which expands IPDiA’s ability to meet current market requirements particularly in the field of medical or aeronautics. Qualification procedure was initiated during the project by launching preliminary reliability studies and it will continue in the coming months.

On top of these R&D results, the other main objective of PICS was the industrialization of this new integrated capacitors technology. Thanks to the partnerships set up, the manufacturability and financial viabilities were ensured by developing adequate industrial tools targeting mass production. The PICS project is a success for all three SMEs and a good example of the benefits brought by the EU funding instrument “Research for the benefit of SMEs”. The SMEs were able to outsource a part of their research to get from RTD performers innovative know-how and cutting-edge technological processes. The project was built to answer the SMEs’ specific needs and a common goal was set up around the new IPDiA capacitors technology and the specific tools (ALD batch tool and etching) required for its commercial exploitation.