Wafer-Level Etch Spatial Profiling for Process Monitoring from Time-Series with Time-LLM

2026-03-24

Technology Category

Machine Learning: Large Multimodal Models (LMMs)Data Mining & Knowledge Management: Mining of Spatial, Temporal or Spatio-Temporal DataPlanning, Routing, and Scheduling: Optimization of Spatio-temporal Systems

Application Category

Graph Algorithms and Modeling for the Web: Foundation models and LLMs for Web-related graphsEconomics, Online Markets and Human Computation: Cost models of using LLMs in production systemsSemantics and Knowledge: Data modeling to support human-machine intelligence, including LLMs agents, intelligent system behavior, explanations, and user-friendly interactions

Abstract

Understanding wafer-level spatial variations from in-situ process signals is essential for advanced plasma etching process monitoring. While most data-driven approaches focus on scalar indicators such as average etch rate, actual process quality is determined by complex two-dimensional spatial distributions across the wafer. This paper presents a spatial regression model that predicts wafer-level etch depth distributions directly from multichannel in-situ process time series. We propose a Time-LLM-based spatial regression model that extends LLM reprogramming from conventional time-series forecasting to wafer-level spatial estimation by redesigning the input embedding and output projection. Using the BOSCH plasma-etching dataset, we demonstrate stable performance under data-limited conditions, supporting the feasibility of LLM-based reprogramming for wafer-level spatial monitoring.

Problem

• wafer-level
• spatial profiling
• plasma etching
• process monitoring
• etch depth distribution

Innovation

• Time-LLM
• spatial regression
• wafer-level etch profiling
• in-situ process monitoring
• plasma etching