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Direct heteroepitaxy and selective area growth (SAG) of GaP and GaAs on Si(100) and Si(111) are implemented by low-pressure hydride vapor phase epitaxy (LP-HVPE), which are facilitated by buffer layers grown at 410–490 °C with reactive gas mixing directly above Si substrates. High-density islands observed on GaP buffer layers on Si result in rough morphology and defect formation in the subsequent GaP layers grown at 715 °C. The impact of growth temperature of GaAs buffer layers on the crystal quality of GaAs/Si is studied. A decreased nucleation temperature significantly improves the morphology and crystalline quality of the overall GaAs growth on Si. It is observed that Si(111) substrates are favorable for both GaP and GaAs growths in comparison with Si(100). In SAGs of GaP/Si and GaAs/Si, the high selectivity innate to HVPE is maintained in the used unconventional growth regime. The spatially resolved photoluminescence mapping reveals the material quality of GaAs/Si is enhanced by defect filtering by SAG. The outcomes of this work will pave the way of III–V/Si integration realized by cost-effective HVPE for photonic device applications., QC 20210323

Direct heteroepitaxy of GaAsP and GaP on GaAs and on Si by low-pressure hydride vapor phase epitaxy (HVPE) is investigated as prior studies for photovoltaics and non-linear optics applications. When growing GaAsP on GaAs, it is found that the ambient gas during substrate pre-heating influences the ternary composition as well as the crystalline quality of the subsequent growth. GaAs0.72P0.28 with bandgap energy of 1.76 eV has been achieved, which would be suitable for a top cell in Si tandem solar cell structures. Growth of GaP was investigated on planar GaAs as a prior study for realizing orientation patterned (OP) GaP on OP-GaAs. Threading dislocations caused by the 3.6% lattice mismatch between GaP and GaAs are suppressed by adjusting the GaCl flow, achieving a low full width at half maximum of 146 arcsec for the X-ray diffraction omega scan. Direct heteroepitaxy of GaAsP on Si aiming for achieving a GaAsP/Si dual junction solar cell is demonstrated. The inherent problem of initiating nucleation during the direct heteroepitaxy of III-V on Si by HVPE is overcome by utilizing the vapor mixing approach to grow a low-temperature GaP buffer layer on Si, followed by a GaAsP layer grown by conventional HVPE., QC 20200603

The number of consumers using social media is increasing globally and social media becomes an important tool for marketers to promote brand marketing campaigns. The advent of social media enables consumers to actively show opinions and attitudes rather than passively receive branded content. On social media platforms, such as Sina Weibo, consumers can comment, forward and post user-generated content engaging with social media, thereby influencing the engagement behaviour of other users. Compared to traditional business-to-consumer communication, consumer-to-consumer communication such as user-generated content may be more likely to gain consumer trust and influence engagement behaviour. In the context of social media engagement, this research examined how social relationships between users moderate the relationship between user-generated content and engagement behaviour, and the impact of engagement behaviour on brand trust, to find out how brands can optimise their social media marketing strategies and promote consumer engagement. This research was based on a quantitative analysis using an online questionnaire distributed to users who have used Weibo, and 93 valid responses were collected. The results show that the perceived informativeness of user-generated content had a greater impact on consumption behaviour, while the perceived entertainment value of the content was more influential on contribution and creation behaviour. In addition, tie strength in social relationships negatively moderated the relationship between the characteristics of user-generated content and creation behaviour. Regarding the benefits of engagement behaviours for brands, only the positive relationship between contribution behaviours and brand trust was supported. Furthermore, brands and marketers should focus on user-generated content in their marketing strategies, seek a balance between informativeness and entertainment value in social media content, and pay attention to the effect of we