Specific Process Knowledge/Lithography/EBeamLithography/EBLProcessExamples

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This page is under construction. In time we will fill it with relevant process examples and relevant data.

Mix-and-match with EBL and UV lithography

Using mix-and-match it is possible to combine EBL and UV lithography using selected resists. Read more on the Mix-and-match page.

Circle arrays by single spot EBL on JEOL 9500

Arrays of circular holes can be created by normal area writing of a mask of circular structures, this is illustrated in the left side of the figure below. In this case the drawn circles are filled with beam shots, just like for any other area based exposure. For large arrays this can however be quite slow and hence it can be faster to write circles with local overexposure of single beam shots, i.e. a setup where the beam is pitched at the required circle pitch and the beam dwells at each site to produce a circle of the required size. In this approach dwell times will typically be in the order of several 100 ns to a few µs.

The single shot approach is illustrated in the center and right parts of the figure below as there are two ways to go about this.

  • Big box approach: This approach is illustrated in the center of the figure below. The mask is a single box of the desired size of the array. The beam is then pitched with the SHOT x, n command where n determines the beam pitch and hence the pitch of the resulting circles. The size of the resulting circles is determined by the dwell time.
  • Small box approach: This is illustrated on the right side of the figure. In this approach each circle is represented by a small 2x2 nm box, hence the pattern is an array of these small boxes and the beam pitch is set higher than the size of the box to produce a single beam shot in each box. Again, the size of the resulting circles is determined by the dwell time.
SingleShot1.png SingleShot2.png Singleshot3.png

Example of the three different approaches for exposing arrays of circles. In all cases the red areas are the areas drawn in the mask file. The small circles indicate beam positions.

Big box approach

Small box approach

Results

SingleShotChart.png

Circle size as a function of pitch and dwell time for exposure at 29 nA.

Single-spot e-beam lithography for defining large arrays of nano-holes

Article on quality control on the JEOL 9500 system

Quality control of JEOL JBX-9500FSZ lithography system in a multi-user laboratory