Objectives 1 paragraph
In this lab our objective was to create a study ………. by use of lithography.
A wafer was prepared for this lab prior, it was composed of a thin layer of Titanium (20
nanometer) with a thicker layer of Aluminum (200 nanometer) on top. Our goal in this lab was to
take this wafer with thin Aluminum/Titanium film, and imprint the design of the thermal sensor
on it using a mask. After etching the excess Al and Ti away, we should be left with only the
sensor. We will continue to elaborate on the steps we completed in this lab and their purpose.
First, we will provide background information on different applications for thermal sensors and
how they are created.
background and motivation of the lab
Photolithography is defined as transferring patterns on a mask to the surface of the silicon
wafer. Alois Senefelder, around 1978 in Germany, was the first one who accidentally discovered
a way to copy scripts onto limestone, called “writing on stone”. A clean impression of the design
was made when a sheet of paper was pressed against the surface of the stone. After then, a lot of
research was conducted, both in industrial and academic level, to develop such a technique .
Among industrial companies, Kasper instruments and Nikon was the first to develop lithography
Generally speaking, lithography can be divided into eight main steps: Wafer cleaning,
prebake, adhesion promotion, photoresist application, soft bake, UV exposure, development and
hard bake. Figure 1 shows the schematic steps in a typical photolithography process.
Photolithography is one of the important steps in semiconductor manufacturing since it
directly affects other fabrication steps especially etching process.
Background (or Principles) 1-3 pages
Introduce the operational principles of the technology or equipment
Describe the process and explain the theories
Cite the references from other publications and resources 2.0 Procedure 1-2 pages
Elaborate on steps performed in lab
Define equipment and/or materials used
Give all necessary equations
Results and Discussion 2-5 pages
Explain the experimental results
Show and explain all necessary data, pictures, tables, and graphs with proper titles, axis titles, legends, etc.
Evaluate results and comment on their accuracy
Evaluate microfabrication processes consider environment factors
Read references and compare your data with existing theories or data
Cite the references from other publications and resources 3.0
Conclusions 1 paragraph Summarize the findings 1.0
References Use the IEEE standard reference format