MONOLITH: Monolithic integration of light emitting devices with Si-ICs using conformal epitaxy

• Research unit: EU RFP
• Project number: 96.0236

Key words (English)

MEL-ARI optoelectronic interconnects for ICs; GaAs-on-Si; conformal vapor phase epitaxy; monolithic integration; microcavity-LEDs

Alternative project number (English)

EU project number: EP 22.614

Research programs (English)

EU-programme: 4. Frame Research Programme - 1.3 Telematic systems

Short description (English)

See abstract

Partners and International Organizations (English)

Thomson CSF (F), Fraunhofer Gesellschaft zur Förderung der angewandten Forschung (D)

Abstract (English)

This project deals with the realization of a building block of future optically interconnected systems, i.e. GaAs light emitting diodes (LEDs) integrated with their silicon drivers. A monolithic integration method, based on the use of the new conformal epitaxy technique for the growth of low defect density GaAs layers on Silicon, will be developed.
The objectives and anticipated results of the project are:
1. To prove the efficiency of the conformal growth technique to integrate monolithically high quality GaAs-based light emitting devices on silicon.
2. To investigate the compatibility between the conformal growth technique and the standard silicon CMOS processing, in particular the conservation of the performances of the silicon ICs during the subsequent epitaxy and LED processes.
3. To evaluate the required modifications on silicon IC design and technology in order to decide on further industrial development of this integration technique.
Within this project, the IMO-EPFL research group is responsible for the design, epitaxial growth and optical characterization of surface emitting microcavity light emitting diodes. The diodes will be integrated on conformal epitaxial layers, deposited on silicon substrates containing the CMOS integrated circuit drivers, and the performance of the complete Si-driver and microcavity LED system will be evaluated.
To date, successful operation of surface emitting microcavity LEDs (MCLEDs) on GaAs and conformal GaAs-on-Si substrates has been demonstrated. Maximum external quantum efficiencies obtained on surface emitting MCLEDs are> 10% for large area devices and > 3% for 24 x 24 um area devices suitable for coupling into optical fibers. Total coupled powers of 270 um into a 100 um diameter fiber have been achieved.
The feasibility of full integration of MCLEDs with 0.8 utm silicon CMOS technology has been shown. The project has been extended for one year to investigate the compatibility of the integration process with an advanced 0.18 um silicon process technology, including multilevel metal interconnects.

References in databases (English)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 96.0236