Investigation of the Mechanical/Thermal Properties of Nano-Scale Silicon Nitride Membranes

Abstract

In micro/nano electro-mechanical system, silicon nitride (SiN x ) membrane has been widely used in sensors, energy harvesting and optical filters because of its mechanical/chemical stability. However, it is necessary to verify mechanical and thermal properties of nanoscale SiNx membranes to ensure the desirable reliability and durability of a device because the properties of nanoscale films vary with thickness which is severely depending on changes in density, grain size, and crystallinity. In this paper, SiN x membranes were fabricated by low pressure chemical vapor deposition followed by reactive ion etching and KOH wet etching. The composition, surface roughness, thickness uniformity and residual stress of the deposited SiN x films were measured to confirm the reliability of the deposition process. Plane-strain modulus, failure stress and emissivity were evaluated by bulge test and heat load test. As a result, the failure stress of the membrane was enhanced by decreasing SiN x thickness while the plane-strain modulus was insensitive to the thickness variation. Through the UV laser heat-load test, it was found that the thermal durability of the thinner membrane deteriorated due to decreased emissivity. To investigate the emissivity depending on membrane thickness, a finite element method simulation was performed based on the experimental results. The calculated emissivity of each membrane coincided with the reported values within 8% difference.

Investigation of the Resistivity and Emissivity of a Pellicle Membrane for EUV Lithography

“…Equation ( 5) represents a resistivity model for thin films that considers the bulk resistivity and the effect of surface and grain boundary scattering [24][25][26]. Here, d is the film thickness, l is the mean free path of an electron, and g is the grain size.…”

“…Therefore, the cooling mechanism by convection and conduction can be excluded and the emissivity can be evaluated from the heat load test results. The emissivity of the pellicle composite was calculated from the absorbed heat load and average peak temperature using the heat transfer equa-tion shown in Equation ( 7), wherein the effects of heat conduction and convection were excluded [12,24,25].…”

“…Furthermore, the heat load test was performed in a the pellicle composite was at the nanometer scale thickne anism by convection and conduction be excluded and from the heat load test results. The emissivity of the pe from the absorbed heat load and average peak temperatu tion shown in Equation (7), wherein the effects of heat c excluded [12,24,25].…”

Impact of thermal expansion coefficient on the local tilt angle of extreme ultraviolet pellicle

“…( 1), considering the absorbance of the pellicle at two different wavelengths. 11 The absorbance (0.1) at a wavelength of 13.5 nm was used for the 19-nm-thick Si 6 N 7 pellicle according to the center for x-ray optics database. 12 α 355 nm was set to 0.0344 based on the spectrophotometer results, and A 355 nm was set to 0.283 cm 2 , corresponding to the area of a 0.6-cm-diameter beam.…”

Сравнительное Исследование Термостойкости Пелликлов На Основе Бериллия

“…Пленки из силицидов металлов (ZrSi 2 , MoSi 2 ) способны выдерживать тепловую нагрузку, сравнимую с той, что выдерживают пленки из p-Si [22], и поэтому не имеют явных преимуществ, в то время как пленки из азотированных силицидов циркония и молибдена превосходят по термостойкости пленки из p-Si (в том числе и p-Si с нанометровыми покрытиями), но менее прозрачны [16]. Пленки из нитрида кремния обладают более высокой термостойкостью, чем из p-Si, однако вследствие того, что ИК-излучательная способность у нитрида кремния еще меньше, чем у поликристаллического кремния, SiN x -пелликлы (толщиной 54 nm) без покрытий выдерживают примерно такую же тепловую нагрузку (менее 80 W эквивалентной мощности в промежуточном фокусе [23]), что и p-Si-пелликлы.…”