Proximity effect (electron beam lithography)

About: Proximity effect (electron beam lithography) is a research topic. Over the lifetime, 940 publications have been published within this topic receiving 8508 citations.

Study of negative electron beam nanoresist HSQ on GaAs substrate

Abstract: The aim of this paper is to characterize Hydrogen Silsesquioxane (HSQ) inorganic negative electron resist on GaAs substrate at 40 keV electron energy. The influence of process parameters on resist profiles was investigated with the aim of obtaining vertical sidewalls. The values of the proximity effect function parameters (β f , β b and η E ) were calculated using Monte Carlo approach. Observation of HSQ resist profiles were done for a set of linewidth dimensions.

Proximity effects correction for sub-10nm patterning node

Abstract: In this communication, we report on our experimental results from the research focused on the application of the electron beam direct writing in the nanometer range. Special care is taken to analyze the forward scattering spread and its influence on the pattering fidelity for patterns with the dimensions in the sub-10nm region. We model, simulate and discuss several different cases of the strategy used in the pattern writing. The sub-pixel address grid is used and the energy beam distribution is analyzed with 1 angstrom resolution. The pre-compensated energy distribution is analyzed from its slope cross-sectional point of view. Additionally, the field factor correction (FFC) dose compensation, the correctness of the built-in FFC compensation for the sub-10nm regime, and its influence on the writing speed is discussed. We map the pre-compensated energy distribution used for the pattern exposure to the developed resist profile modeled by the spline approximation of the experimentally acquired resist contrast curve. The newly established development process for the hydrogen silsesquioxane (HSQ) resist has been tested and applied in its optimal way. Successful sub-10nm patterning with the dimension controllability better than 5% of the critical dimension (CD) was achieved. The experimental setup use JBX-9300FS (used @ 100keV) as the exposure tool, and the HSQ (XR-1541) as the resist. The energy intensity distribution (EID) function used for the proximity effects compensation is calculated by CHARIOT simulation engine.

Method for compensating proximity effect of electron beam

Abstract: PURPOSE:To compensate for a proximity effect, by irradiating each part of a reactive layer, which is formed by drying a reactive material that is attached to a substrate, with an E beam, and thereafter burning the reactive layer. CONSTITUTION:A liquid reactive material is poured on an upper surface 12 of a substrate 14. Then a reactive layer 10 is formed by treatment using a suitable method such as burning. The surface of the reactive layer 10 is scanned so as to cross the surface with an E beam lithography. Irradiated parts 22a-22e have different widths by back scattered electrons even if energies projected from E beams 16a-16e are at the same energy level. After the irradiation, burning is performed. Then, the irradiated parts 22a-22e have the approximately same width of, and non-irradiated parts 24-34 have the approximately the same width Sf. This is because molecules are moved from the non-irradiated parts 24-34 to the irradiated parts 22a-22e caused by the burning after the irradiation.

Alignment method of low-energy electron-beam direct writing system EBIS using voltage contrast image

Abstract: We have developed the EBIS (Electron Beam Integrated System), which is a character projection (CP) type low-energy electron-beam direct writing (LEBDW) system. In this system, the proximity effect due to backscattering electrons is very small under the condition that the energy of primary electron is 5 keV. However, there is a serious problem, in that the signal of the mark buried under a thick insulator couldn't be detected. To overcome this problem, we adopted a mark detection method using Voltage Contrast (VC) image with negative charge on the sample surface. So far, we have detected the signal of alignment mark buried under 600nm-thick (nmt) tri-layer resist using VC image on EBIS. Then we exposed overlay patterns with alignment using the mark detection with VC image. The mark image is very clear with a sufficiently high contrast. The asymmetry originating from VC is mitigated by means of FB scanning. Using this VC mark detection method, EB drawing was performed with alignment with 600nmt tri-layer resist on Si substrate. Moreover, VC mark detection with 600nmt tri-layer resist on the substrates of back-end-of-line (BEOL) of logic device was performed and the mark images with sufficient contrast were obtained. Although the characteristic distortion of VC image exists, mark detection is possible by using X/Y separate scanning, which consists of X-direction scanning to get an X position and Y-direction scanning to get a Y position in non-charged area.

Estimation of optimum EPL mask biases in consideration of Coulomb beam blur

Abstract: The authors discuss the dependence of the beam blur on the pattern density and estimate the amount of mask bias required to correct the proximity effect in consideration of the beam blur difference in electron-beam projection lithography.