In the past few decades, leading edge logic technology scaling has been the main driver for semiconductor metrology developments. As traditional device scaling is slowing down, the semiconductor industry is focusing also on heterogeneous integration approaches, which leverage advanced packaging technologies to integrate devices designed and manufactured separately using the most suitable process technology for each device. Heterogeneous integration presents significant metrology challenges, which are different from what is encountered at the logic device level in terms of materials and specifically dimensions. Large-scale 3D structures need to be characterized with unprecedented accuracies and advanced optical techniques play a pivotal role. In this paper, some metrology challenges in heterogeneous integration are introduced and discussed related to TSV characterization including depth and reveal height, wafer bonding measurements, and dimensional and overlay metrology for processing leading to bump receivers and bump formation. Current capabilities utilizing various imaging and interferometry techniques are presented and their limitations discussed.
3-dimensional chiplet device architectures are expected to provide improved device performance, efficiency, and footprint beyond what is capable with 2-dimensional scaling technologies. Thick resist lithography of damascene and plating resists, as well as organic dielectric materials, plays a critical role in chiplet integration. However, thick resist lithography requires viscous resist solutions, specialized tooling, and long processing times. This makes patterning using these resists inherently prone to uniformity issues, which has become a crucial issue for scaling. This work highlights two strategic areas of thick resist patterning development: improved resist coating methods; and enhanced focus control during exposure. Herein, we show a track-based method for carefully controlled uniformity of the resist coating thickness, with some sacrifice of through-put. In addition, we show stepper-based focus methods to account for die level variations in resist and wafer thickness, as well as local topography. Combined, these provide precise cross-wafer control of thick resist dimensions.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.