Microelectronics @ Northrop Grumman

In summer 2025, I had the privilege of working with the Electron Beam Lithography (EBL) Team at Northrop Grumman.

Lithography is the process of creating patterns on a semiconductor wafer using a beam of photons, or in the case where nanometer precision is required, electrons. Our team fabricates the smallest component of a microprocessor: the gate of a transistor. The gate is the key component that controls the flow of current through the transistor, and is typically only a few nanometers wide.

With such scale, comes the challenge of patterning the gate with high precision. Anti-charging agents are conductive polymers that you dispense onto the wafer in a spin coat + bake process. The EBL fires beams of electrons onto the wafer. If the wafer is not discharged, it too contains electrons. Electron meeting electron = repulsion => inaccurate gate patterns. These anti-charging agents work to prevent EBL drift, and therefore promote better gate alignment, and higher chip yield. For various reasons, our team wanted to replace our wafer anti-charging agent. It’s commonly known that in manufacturing, changes to a single step in the process can have a cascading effect on the entire line. This applies to Northrop’s foundry at an extreme magnitude, due to the nature of dealing with nanometer precision.

I examined and validated 3 wafer anti-charging agents by running a series of experiments to ensure it was as effective as the old one. I conducted 40+ resistivity, transistor gate alignment, and spin curve experiments. I studied every environmental variable that could affect the results: temperature, humidity, time, machine operation, spin speed, etc. Ultimately, I saw just how delicate the semiconductor manufacturing process is (especially EBL), and how crucial it is to be mindful of every variable in the workspace. Overall, I optimized wafer-coating procedures and evaluated exposure performance across test lots, yielding $26,000 in projected annual company savings.