MOVPE growth of GaN on patterned 6-inch Si wafer

Abstract

We demonstrate that thicker layers can be achieved in gallium nitride (GaN) epitaxy by using a patterned silicon (Si) substrate compared to a planar Si substrate. GaN films were grown by metalorganic vapour-phase epitaxy on 6-inch Si (111) substrates patterned with arrays of squares with various corner shapes, height and lateral dimensions. Stress spatial distributions in the GaN pattern units were mapped out using confocal Raman spectroscopy. It was found that the corner shapes have an effect on the uniformity of the stress distribution. Patterns with round corners were found to have more uniform stress distribution than those with sharp corners. The largest crack-free square size for a 1.5 μm thick GaN film is 500×500 μm 2 .

Полуполярные Широкозонные III-N-слои На Кремниевой Подложке: Эпитаксия С Контролем Свойств Структур (Обзор)

“…Обнаружено, что возникает паразитная реакция Ga с кремнием в процессе эпитаксии MOCVD через тонкий буферный слой AlN (Ga melting etching) [41,42], а низкая подвижность адатомов Al как на поверхности кремния, так и на поверхности нитрида алюминия затрудняет структурную перестройку адатомов и делает поверхностную морфологию эпитаксиальной пленки AlN шероховатой [43].…”

WITio: A MATLAB data evaluation toolbox to script broader insights into big data from WITec microscopes

“…Another collaborative work in 2020 involved CRM-based 2-D stress distribution imaging of GaN mesas grown by metalorganic vapor-phase epitaxy on patterned 6-inch Si wafers [7]. These scans were spectrally calibrated and post-processed by semi-automated WITio v1.2.0 scripts for publication [7].…”

“…For the previously stated reasons, WITio improves the pursuit of many existing research questions, for example, systematic quantitative analysis of material stress [6,7]. Its fruit so far would be multiplied hundredfold even if only a fraction of the WITec community adopted the toolbox.…”

GaN MSM structure UV photodetector detector based on nonplanar Si substrate and its performance optimization

“…In addition to the success achieved by introducing gradient buffer layers between crystal Si and GaN, growing GaN nanostructures on patterned Si substrates was also proved to be a promising route to reduce the defect density of dislocations, stacking faults and microcracks [14]. The successful demonstrations show that by using patterned Si substrates, crack-free GaN films with a thickness of 1.5 µm and an area of 500 × 500 µm 2 were prepared [15], and high-quality GaN films with a tensile stress reduction over 31% compared with planar Si substrate were obtained [16].…”