Göktaş, Oktay; Çakıroğlu, Dilek; Yıldırım, Özal; Göktaş, Nebile Işık

With the advance of nanotechnology, the demand for very dense nanopatterns over large areas continuously increases. Electron beam lithography is one of the main tools to realise this type of nanopattern. In this study we investigate the effect and interrelation of dose and development time for electron beam resist poly(methyl methacrylate) (PMMA) for the realisation of very large area and very dense nanopatterns. For this purpose a pattern consisting of a lattice of holes with radius of 80 nm and lattice constant of 200 nm has been designed, electron beam lithography is realised on a thin resist and a detailed SEM image inspection of the pattern is recorded. Hough transform, a pattern recognition method for the digital images, is applied to SEM images to measure the radii of the holes on the images. Interrelation between dose and development time is investigated. It is found that for a very large area of dense nanopatterns the lithographic process works better for development times shorter than typically used ones.

İncele

Göktaş, Oktay; Kaya, İsmet İnönü; Göktaş, Nebile Işık

İki boyutlu elektron sistemleri zengin ilginç özellikler barındıran sistemler olarak yoğun bir araştırma konusu olmuşlardır. Bu sistemlerde nano teknolojinin sunduğu olanaklar da kullanılarak yepyeni özellikler sergileyen aygıtlar hazırlanmış ve deneyler yapılmıştır. Balistik tranzistörler, Kuantum nokta kontaklar, kuantum noktalar ve elektron interferometreleri bu aygıtlardan bazılarıdır. Bu projede AlGaAs/GaAs hetero yapıların ara yüzeyinde oluşan iki boyutlu elektron sistemlerinde, MZ interferometreler ve kesikli enerji seviyelerine sahip olmalarından dolayı yapay atom olarak da adlandırılan kuantum nokta sistemlerinin fabrikasyonu yapılmış ve incelenmiştir.

İncele

Göktaş, Oktay; Işık Göktaş, Nebile

In this study, we use Hough Transform as a test tool to investigate the quality of the electron beam lithography. A graphene like thin film of metal layer is fabricated on top of GaAs substrate by electron beam lithography. Hough Transform is applied to the SEM images of the fabricated pattern and the quality of the lithography process is quantitatively investigated. All the existing critical dimensional measurements on the SEM images which would otherwise take several days are done in a single step. The power and potential use of Hough Transform for the SEM image inspection especially for the quality test of nano-patterning processes is demonstrated.

AtıfScopus3·WoS3·OpenAlex4

İncele