Lim Yi Hui

Lim Yi Hui

Dry Etch Process Owner

My company and my job

Since graduating from NUS two years ago, I have been working for Micron, a leading memory and semiconductor company. Memory is made through a wafer fabrication process where a silicon wafer undergoes eight steps repeatedly for more than 20 cycles before the finished wafer is produced.

Dry etch is one of the eight steps of the process, and I am a dry etch process owner. My main responsibilities include working on yield-and-cycle time improvements and deviation prevention projects for the processes under my care. Currently, I am a part of an exciting team focusing on 3D NAND process optimisation, one of our newest technologies.

How I got my job

The entire interview process took about half a day. I was given a logic test, followed by four rounds of interviews with several dry etch managers, and then a final interview was with the fabrication director.

Preparation for the interview was important, but I also had to play up my strengths to set myself apart. I displayed commitment and consistency by citing my CCA record – I was in dance since Primary 1 through to university. Thinking back, displaying commitment during the interview was extremely important as it takes at least 6 months for an engineer to learn the ropes of their work.

The highs and lows

I enjoy the autonomy that I am given in my work. There is always room to explore new solutions to existing yield issues, which gives me a great sense of accomplishment when I succeed. Moreover, I am blessed with helpful colleagues and encouraging supervisors. I also find a sense of belonging to Micron when I get the chance to support events outside of my core role.

I was also ecstatic when I discovered the root cause to a problem and successfully implemented a solution on my own. Knowing that I made a significant contribution to the company created a sense of pride and achievement that was most memorable.

However, being in an extremely fast-paced industry, there is a need to embrace change. I have already gone through three rounds of job responsibility changes, each entailing a steep learning curve and quick adaptation to a new environment.

Training and support

My training started off with two weeks of in-classroom training where key practices, concepts, and systems were introduced. Subsequently, I was attached to the dry etch manufacturing team to understand more about their roles, responsibilities, and priorities. The third part was equipment training, where I had the opportunity to witness tool conversions, new tool installations and maintenance activities. Lastly, I was attached to an experienced process owner for 2 weeks for process training.

Work-life balance 

Within dry etch, we occasionally organise after-work activities such as badminton, basketball, and karaoke. Our working hours also vary depending on the urgency of the tasks I have at hand. That said, my supervisors consistently encourage us to leave work on time.

Some advice 

Recently, I was tasked to transfer a process from an existing series of equipment to a more advanced series of equipment under an extremely tight timeline. I made the choice to work beyond working hours and on the weekends – which led to the success of the project.

When difficult tasks are presented to you, embrace them and see them as opportunities to excel. Have faith in finding solutions to even the most challenging problems, and you will find them.