Search results
Results From The WOW.Com Content Network
Immersion lithography is a technique used in semiconductor manufacturing to enhance the resolution and accuracy of the lithographic process. It involves using a liquid medium, typically water, between the lens and the wafer during exposure.
High-index immersion lithography is the newest extension of 193 nm lithography to be considered. In 2006, features less than 30 nm were demonstrated by IBM using this technique. [72] These systems used CaF 2 calcium fluoride lenses. [73] [74] Immersion lithography at 157 nm was explored. [75]
Multiple patterning with immersion scanners can be expected to have higher wafer productivity than EUV, even with as many as 4 passes per layer, due to faster wafer exposure throughput (WPH), a larger number of tools being available, and higher uptime.
This method, called immersion lithography, is the current cutting edge of practical production technology. It works because numerical aperture is a function of the maximum angle of light that can enter the lens and the refractive index of the medium through which the light passes. When water is employed as the medium, it greatly increases ...
The emergence of immersion lithography has a strong impact on photomask requirements. The commonly used attenuated phase-shifting mask is more sensitive to the higher incidence angles applied in "hyper-NA" lithography, due to the longer optical path through the patterned film. [15]
Immersion Lithography has been generally accepted as the lithography technology for the next several silicon generations. Impurities in the water such as dissolved gases and ionic salts can change the index of refraction, which directly affects image quality projected onto the wafer.
Hence, it is commonly used for the origination of master structures for subsequent micro or nano replication processes [4] (e.g. nanoimprint lithography) or for testing photoresist processes for lithography techniques based on new wavelengths (e.g., EUV or 193 nm immersion). In addition, interfering laser beams of high-power pulsed lasers ...
The test chips had a cell size of 0.182 μm 2, used a second-generation high-κ gate dielectric and metal gate, and contained almost two billion transistors. 193 nm immersion lithography was used for the critical layers, while 193 nm or 248 nm dry lithography was used on less critical layers. The critical pitch was 112.5 nm.