Review—Important Considerations Regarding Device Parameter Process Variations in Semiconductor-Based Manufacturing

Abstract

This paper reviews the topic of the device parameter variations using semiconductor-based manufacturing of micro- and nano-devices. There is considerable misunderstanding about the precision of these types of manufacturing methods and that smaller does not always mean more precise. This issue is very important to many types of devices made using semiconductor manufacturing, particularly those having analog functionality including MEMS, NEMS, photonics, analog ICs, and nanotechnologies. It also is getting increased attention in digital ICs as the gate lengths have decreased. It is shown that the relative variations using these manufacturing methods are generally larger in magnitude compared to more conventional methods of production such as traditional machining operations. Moreover, since many of the devices made using semiconductor-based manufacturing methods have analog-functionality, device parameter variations can have a magnified impact on the variations exhibited in the device output behavior. Methods to estimate the impact of device parameter variations on the device output behavior are given, including an analytical method and Monte Carlo analysis. The impact of these variations on the manufacturing yield is explained and demonstrated. Lastly, a number of techniques that can be used to manage these device parameter variations so as to improve the manufacturing yield are given.