Heteroepitaxy of In0.53Ga0.47As on GaAs substrate by low pressure metalorganic chemical vapor deposition for the OEIC applications
Introduction
The InP-based material has demonstrated great potential for long-distance communications [1], [2], high frequency electronic devices [3], etc. However, InP suffers from several drawbacks that include higher fragility, less mature processing technologies, and smaller available wafer sizes as compared to GaAs. The advantages of lower cost and robustness enjoyed by GaAs have motivated research endeavors into the growth of InP layer on GaAs substrate.
However, two major problems that will be encountered with during InP/GaAs heteroepitaxy are the large lattice mismatch of 3.7% and the difference of 1.8×10−6 K in the thermal expansion coefficient. It is well established that lattice mismatch and different thermal expansion give rise to interfacial strain and structural defects mainly in the form of dislocation, which will cause the degradation of the devices. Thus, several approaches, such as LT buffer layer [4], [5], [6], composition graded buffer [7], [8], thermal cycle annealing (TCA) [9] and strained-layer superlattice buffer layers [10], [11], etc. have been employed in recent years. LT buffer layer approach has been adopted most widely because of simple process procedure and easy control.
In the previous works research on InP/GaAs heteroepitaxy by LT buffer scheme, the main attentions have been paid to simply improving the material characterization through adding the normal InP layer thickness above LT InP buffer. For examples, Hirokawa [4], Radhakrishnam [5], and Takano [6] et al. grew the thick normal InP layer (1.5–6 μm) on the top of the LT InP buffer. But such hereoepitaxy processes can not be employed to fabricate the monolithic OEIC devices. So the normal InP layer is reduced to 400 nm in the paper, the better result is realized through optimizing the buffer layer schemes, which is a tradeoff in the devices application and material growth.
In this paper, the heteroepitaxy approach based on LT InP metamorphic buffer has been studied intensively, the normal InP layer is reduced to 400 nm. We report the successful growth of device-quality InP/In0.53Ga0.47As/InP sandwich structures on GaAs substrate using low pressure metal-organic chemical vapor deposition (LP-MOCVD). Scan probe microscope (SPM), high resolution X-ray diffraction (HRXRD), and photoluminescence (PL) measurements have been carried to characterize the samples with different LT metamorphic buffer layer.
Section snippets
Experimental procedure
The heteroepitaxy samples were grown on semi-insulating GaAs(100) substrates by TSSEL 3×2″ CCS LP-MOCVD system. Trimethylindium (TMIn) and Trimethylgallium (TMGa) were the group III organic–metallic sources, arsine (AsH3) and phosphine (PH3) were the group V hydride sources. The carrier gas was H2 purified by palladium-diffusion cell, and total carrier flowrate was 12,000 sccm. The reactor pressure was kept at 100 Torr, and the rotation speed of susceptor was 100 rpm. The V/III ratios were 100,
Result and discussion
HRXRD (ω–2θ scan of no. 7 sample is shown in Fig. 2. Due to the large strain existing between InP-based epilayers and GaAs substrate the diffraction peak of epilayers is obviously broadened. A group of samples listed in Table 1 have been grown and studied with the intention to find out the optimal thickness of the LT buffer grown at 400 °C. The selective thickness of LT InP buffer is 10, 15, 35, 60 and 150 nm for sample 1–5, respectively. The FWHM values of XRD (including epitaxy layers and
Conclusion
In order to investigate the compatibility of heterogeneous semiconductor material and fabricate long-wavelength InGaAs PIN photodetector on GaAs substrate, InP/In0.53Ga0.47As/InP sandwich structures with different LT InP metamorphic buffers have been grown on GaAs substrates. Meanwhile, HRXRD, room-temperature PL and SPM measurements have been also carried out to evaluate the quality of the heteroepitaxy samples. Based on the optimized growth conditions, the best FHWM value of 512 arcsec and 51.7
Acknowledgments
This investigation is funded by National Basic Research Program of China (NO. 2003CB314901) and High-Tech Research and Development Program of China (No. 2003AA31g050, 2003AA312020). The authors would like to acknowledge Professor Guangdi Shen (Beijing University of Technology), Research fellow Xiaoyu Ma (Institute of Semiconductor, CAS) and Professor Wang (Institute of Chemistry, CAS) for the measurements.
References (14)
- et al.
Characterization of InGaAs/InP single quantum well structure on GaAs substrate with metamorphic buffer growth by molecular beam epitaxy
J. Cryst. Growth
(2004) - et al.
Two-step growth of InP on GaAs substrates by metalorganic vapor phase epitaxy
J. Cryst. Growth
(1996) - et al.
Improvement of InP crystal quality grown on GaAs substrates and device applications
J. Cryst. Growth
(1991) - et al.
High temperature 1.55 mum vertical cavity lasers through wafer fusion
IEEE J. Sel. Top. Quantum Electron.
(1997) - et al.
GaAlAs/GaAs metamorphic bragg mirror for. long wavelength VCSEL's
Electron. Lett.
(1998) - et al.
Long-wavelength receiver optoelectronic integrated circuit on 3-inch-diameter GaAs substrate grown by InP-on-GaAs heteroepitaxy
Jpn. J. Appl. Phys.
(1994) - et al.
Hetero-epitaxial growth of InP on a GaAs substrate by low-pressure metalorganic vapor phase epitaxy
Appl. Phys. Lett.
(1988)
Cited by (17)
Epitaxial lateral overgrowth of InP/GaAs (1 0 0) heterostructures by metalorganic chemical vapor deposition
2007, Microelectronics JournalImproved InAsP metamorphic layers grown on an InP substrate using underlying InP grown at low temperatures
2007, Semiconductor Science and TechnologyMetamorphic growth of 1.55 μm InGaAs/InGaAsP multiple quantum wells laser structures on GaAs substrates
2015, Chinese Optics LettersDirect growth of GaAs-based long-wavelength (1.55μm) InGaAs/InGaAsP multiple quantum wells laser
2014, Asia Communications and Photonics Conference, ACPC 2014