Lab report

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 [2].

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