Deep UV laser induced periodic surface structures on silicon formed by self-organization of nanoparticles

Abstract

We have investigated the formation of laser-induced periodic surface structures (LIPSS or "ripples") on silicon upon excitation with p-polarized excimer laser pulses in the deep ultraviolet region (λ = 193 nm, 20 ns). Well-pronounced ripples with a period close to the laser wavelength were observed for pulse numbers N ≥ 100, and the ripple period increased with the angle of incidence. While these results seem to be qualitatively consistent with the standard Sipe-theory, we observed a fundamentally different ripple formation mechanism and ripple morphology. At low pulse numbers, isolated nanoparticles with a size of a few tens of nanometers are observed at the silicon surface, which then start to agglomerate in 2D and self-organize to form ripples with a very shallow modulation depth as the pulse number increases. Employing a recently developed plasmonic model based on the propagation of a surface plasmon polariton on a rough surface, we demonstrate excellent quantitative agreement of the evolution of the ripple period with incidence angle. Finally, we show that surface regions exposed to lower laser fluence feature micro-and nanopores, which give rise to pronounced photoluminescence (PL) emission in the visible spectral region, as opposed to the nanoparticle-based ripples not showing PL.

F2 Laser-Induced Micro-Reticulated Structural Changes of Amorphous Carbon Thin Films

“…A laser additive manufacturing process based on thermal processing and non-thermal materials processing using ultrashort pulse lasers has been actively studied recently [1][2][3][4]. Besides these works, pulsed lasers that oscillate in the ultraviolet (UV) region, although the pulse width of the laser is tens of nanoseconds, are also capable of precise materials processing with no heat-affected zone of around the processing area [5][6][7]. In UV lasers, a pulsed laser that oscillates in the vacuum ultraviolet (VUV) region with a wavelength of 200 nm or less can induce photochemical processes in many materials, enabling fabrication of novel three-dimensional microstructures [8].…”

Nanosecond laser-induced controllable periodical surface structures on silicon

“…People have shown extensive interest in the formation mechanism and process of LIPSS, especially on the silicon (Si) surface. Si being a key material in electronics and optical communications, strategies for turning Si into a material that allows light emission are of great interest [17] . Besides, porous Si has been identified as a suitable candidate to provide efficient luminescence due to the presence of crystalline Si nanostructures.…”

Поляризационно-Зависимая Филаментация Фемтосекундных Лазерных Импульсов В Синтетическом Алмазе

“…Одним из перспективных для науки, техники и промышленности способом является модификация материала ультракороткими лазерными импульсами различной длительности. В рамках данного способа, очевидно, что эффективной технологией является нано-и микроструктурирование на поверхности [1][2][3][4] и в объеме материала с помощью прямой лазерной записи [5][6][7][8][9]. Эта технология позволяет записывать наноструктуры различной формы и конфигурации, производить дифракционные оптические элементы, генерировать микродефекты в объеме материала.…”