| About this Abstract |
| Meeting |
2011 Electronic Materials Conference
|
| Symposium
|
2011 Electronic Materials Conference
|
| Presentation Title |
JJ1, Growth Investigations of Lattice-Matched III/V Compound Materials
on (001) Si Substrate for Optoelectronics |
| Author(s) |
Bernardette Kunert, Sven Liebich, Martin Zimprich, Andreas Beyer, Stefan Ziegler, Kerstin Volz, Wolfgang Stolz |
| On-Site Speaker (Planned) |
Bernardette Kunert |
| Abstract Scope |
The monolithic integration of III/V compound materials on Silicon (Si) substrates moves back into focus of interests after a long history of research. In particular the application for high-mobility n-channel materials in Si-based CMOS transistors as well as for optoelectronic devices is of rising importance. In the latter case the realization of III/V laser diodes on Si substrate with sufficient life time could finally allow for the monolithic combination of optical data processing with the mature Si microelectronic technology and therefore open up a completely new field of micro-chip functionalities. One of the major obstacles in the hetero-epitaxy is the large lattice-mismatch between most common III/V compound semiconductor materials and Si, which leads inevitably to the formation of misfit- and threading dislocations, which is most critical for any device performance. In contrast, the lattice-mismatch between GaP and Si is very small and offers the immense advantage in dislocation-free monolithic growth of GaP on Si substrate by the incorporation of a few percentages of Nitrogen (N) or Boron (B). However, because of the indirect band gap of GaP this approach has been mainly ignored in the past. The novel dilute nitride Ga(NAsP) based on GaP has been especially developed for the lattice-matched and defect-free integration of a direct band gap material on Si. The high As concentration of the quaternary compound material guarantees the direct band gap formation whereas the incorporation of N enables the adjustment of the lattice constant of Ga(NAsP) towards the one of Si. Optical gain measurements of Ga(NAsP) quantum well (QW) structures reveal excellent optical properties comparable to standard III/V laser materials. Therefore, the novel Ga(NAsP) laser material offers an entire new approach for the defect-free integration of optoelectronic devices on Si substrate.
In this paper we discuss growth investigations using metal organic vapour phase epitaxy (MOVPE) for the deposition of Ga(NAsP) QW laser structures lattice-matched on (001) Si substrate. Electrical current injection involves the growth of p- and n-doped cladding layers based on (BGa)P. The quaternary barrier material (BGa)(AsP) ensures a better carrier and light field confinement in the Ga(NAsP)/(BGa)(AsP) based separate confinement hetero-structure (SCH) of the laser diode. Due to the difference in the thermal expansion coefficients of III/V compound semiconductors and Si, each device layer requires a precise strain-management at growth temperature. High-resolution X-ray diffraction (XRD) analysis in line with transmission electron microscopy (TEM) studies did not show any indication for dislocation formation in the several micrometers thick III/V laser device grown on (001) Si substrate. Structural and optical properties of these first electrical pumped laser devices will be introduced and discussed in detail. |
| Proceedings Inclusion? |
Undecided |