Energy Efficiency Project – Learning Launch

Challenge

I am working as Principal Mechanical Engineer in my current organization. My organization is in the  business of design, manufacture and supply of semiconductor fabrication equipments for namely, plasma  etch, CVD coating, PVD coating, thermal processing of Si wafer etc. I am a subject matter expert in thermal  design, product development and R&D of the device components and systems. My team comprise of  several multi-disciplinary experts from mechanical design, controls, software, electrical, sourcing etc.

One of the major challenge of operation of semiconductor fabrication equipments is its poor environment  foot-print. The equipments consume significant electricity, cooling water and also has gas and fine particle  emission challenges. Energy efficiency of the equipments are quite low (may be as low as 20%). Historically  semiconductor equipments technology have been evolved and developed with prime focus on  performance to meet escalating demand of memory chips. Energy efficiency was secondary requirement.

However, in recent times emerging competition in the market and increasing Government regulation on  emission and facilities consumption has forced the customers and supply organizations to focus on  reduction of energy consumption and increase efficiency. My engineering group was challenged by a  major customer to reduce heater power consumption of a system by around 30% to meet Govt restriction  on electricity supply in a major semiconductor fab shop.  Customer had a very strict deadline and had  needed a solution with < 0.05 % failure probability.

Selection

My organization launched a design for environment (DfE) project to meet the above customer challenge.  The DfE team did a brainstorming of several concepts of energy saving. The concepts were evaluated using  QFD, Pugh Matrix, and Risk Assessment tools. When we down-selected one of the most probable concept  which can have differentiated value and has best probability to meet energy efficiency target. But we had  several unknowns: (1) how to know if the concept is achievable?  (2) What is the probability of success?  (3) what is the effect and alternate method if we fail to meet target? (4) Will there be any degradation of  device performance? (5) How to convince customer with alternate design?

Considering the strict deadline and almost NIL margin for failure, team decided that design thinking tool  Learning Launch may be the best way to approach to quickly test the idea and demonstrate a prototype  solution to customer.

Application:

The baseline design (current design) use a conservative approach of supplying high constant flow coolant  in the system and then control the heater power to meet system temperature set point. The concept to  test was can we reduce the coolant flow rate and heater power both simultaneously and meet the same  set point temperature. Theoretically it is possible as with reduced coolant flow rate we remove lower heat  from system and hence we will need lesser heat input from the heater. It is a win-win scenario as we save  energy from both lower coolant flow and lower heater power without sacrificing temperature.

A prototype test facility was developed, and the above concept was tested for different operation recipe.  We tried to reach the minimum coolant flow rate and heater power possible. System response (both  steady state and transient) were observed and benchmarked against baseline. Overall energy balance of  the system was computed and energy saving with respect to baseline scenario was measured. Team  achieved energy saving better than 30%, which meets customer requirement. Experiments were repeated  for several conditions and complete database of experimental results were developed. DOE (design of  experiment) analysis and statistical regression analysis were carried out to measure confidence level to  meet the target. The complete prototype tests could be completed within 2 months’ time frame, well  within schedule.

Insight:

After the learning launch tests, the team could successfully demonstrate that the concepts can work in  actual tool and meet the customer energy efficiency target. The learning launch tests gave the team  sufficient confidence level on the success rate of the concept. Through the tests team also identified  opportunity of development of ANN (artificial neural network) based controls instead of traditional  closed-loop PID control, which may provide more optimized heater power management. The team also  identified scope of application of the concept into several other equipments which operates in similar  way. The team proposed the concepts to upper management and customer and got buy in.

Approach:

The team successfully applied design thinking learning launch tool on the energy efficiency improvement  of an already developed, time tested and mature product. Through this exercise the team realized new  opportunity of using the tool at the concept design level of new products. Instead of going through  complete product development cycle and risk failure at later stage, we can explore using the learning  launch tool at concept evaluation stage and fail fast or get success, which can significantly expedite  product development cycle and meet customer requirement in specific way.

