Room-temperature infrared sub-band gap photoresponse in silicon is of interest for telecommunications, imaging and solid-state energy conversion. Attempts to induce infrared response in silicon largely centred on combining the modification of its electronic structure via controlled defect formation (for example, vacancies and dislocations) with waveguide coupling, or integration with foreign materials. Impurity-mediated sub-band gap photoresponse in silicon is an alternative to these methods but it has only been studied at low temperature. Here we demonstrate impurity-mediated room-temperature sub-band gap photoresponse in single-crystal silicon-based planar photodiodes. A rapid and repeatable laser-based hyperdoping method incorporates supersaturated gold dopant concentrations on the order of 10 20 cm À 3 into a single-crystal surface layer B150 nm thin. We demonstrate room-temperature silicon spectral response extending to wavelengths as long as 2,200 nm, with response increasing monotonically with supersaturated gold dopant concentration. This hyperdoping approach offers a possible path to tunable, broadband infrared imaging using silicon at room temperature.

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Competing relationships and a lack of collaboration are common in the construction industry. Consequently many reasons, such as lack of trust, unfair risk sharing and ineffective communication are highlighted by actors as challenges in the construction sector. Collaboration has been demonstrated as a solution for these challenges for the construction industry. However, collaborative environments are still far from effective in emerging economies with a lack of research and information available for such countries. We have used the Kurdistan region of Iraq to investigate and explore these challenges using systematic enquiry, utilising quantitative and qualitative methods. This article aims to explore these challenges, by reviewing past literature and investigating construction practices to better quantify those factors that underlie collaboration. A comprehensive review of the literature was conducted to identify the most critical factors. Then, a questionnaire was used to survey the opinions of practitioners, analysed through Exploratory Factor Analysis. Six factors were identified: project vision, participant behaviour, communication, relationship definition, contractual agreements and systematic process. Additionally, the paper provides suggestions as to how industry might apply such factors. This article contributes to a scarce literature regarding construction projects in Kurdistan region and emerging economies in general. Keywords -Collaboration, critical factors, construction, project management, factor analysis, emerging economies, Kurdistan, Iraq. overruns, win-lose culture and adversarial relations (Chan et al. 2004). To overcome the issues of TCM, PM has been used. PM models try to control cost, time and quality in a project-based system to achieve client needs; however, this approach also has faced many difficulties (Shen and Wu 2005).After an investigation to solve the problem of fragmentation and underperformance in the UK construction industry (Latham 1994), partnering was suggested as a solution to replace traditional methods of project delivery. Partnering delivered better results than traditional approaches to project management. However, relationships in partnering still need to be improved to overcome the underperformance of construction industry projects (Meng 2012).Many authors have insisted that the construction industry needs to improve collaboration and to adopt new ways of working to remain competitive and meet the expectations of increasingly demanding clients (Shelbourn et al. 2007;Cao et al. 2015;Morrell 2015).While problems of fragmentation and lack of collaboration in construction exist globally, the case is more severe in developing economies, where the construction sector is more fragmented. Additional problems confront construction projects in these countries, compared to developed economies, which include social, cultural, organisational, economic and process-related obstacles (Ofori 2000;Elkhalifa 2016;Haron et al. 2017). This observation is apparent in the Kurdistan region of I...

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