Resistor Trench With Metal Gate Integration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The integration of resistor fabrication with transistors having metal gates in semiconductor manufacturing is complex due to the difficulty in combining different semiconductor device manufacturing methods, particularly in incorporating resistors with polysilicon and silicide layers into metal gate technologies.
Innovation Solution
A method involving the formation of a resistor trench on a substrate with a work function metal layer and metal bulks at its ends, filled with a filler material, which allows for the integration of resistors with transistors having metal gates, enabling easy integration with various processing approaches like gate last and high-k first processes, and allowing resistance modulation through filler doping.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If traditional polysilicon and silicide layers are used for resistors, then resistor functionality is achieved, but integration with metal gate transistors becomes complex and difficult
Solution Approach 1:
The patent merges the resistor fabrication process with the metal gate transistor fabrication process by using the same metal gate electrode as the resistor structure. The metal gate electrode serves dual purposes: as the control electrode for the transistor and as the resistive element for the resistor, eliminating the need for separate polysilicon and silicide layers and simplifying the overall fabrication process.
Solution Approach 2:
The metal gate electrode is designed to perform multiple functions simultaneously: it acts as the control electrode for the transistor, provides the resistive element for the resistor, and serves as a common structural component for both devices. This multi-functionality reduces the number of fabrication steps and materials required, directly addressing the integration complexity issue.
2Reliability
If metal gates are used to replace polysilicon gates, then transistor performance increases, but the integration of resistors with different manufacturing methods becomes more difficult
Solution Approach 1:
The patent combines the resistor structure with the metal gate transistor structure by using the metal gate electrode as the resistive element. This merging approach allows both high-performance metal gate transistors and functional resistors to coexist in the same device without requiring separate fabrication processes, thereby maintaining transistor performance while reducing integration complexity.
Solution Approach 2:
The device is segmented into distinct functional regions: a transistor region where the metal gate electrode functions as a control electrode, and a resistor region where the same metal gate electrode functions as a resistive element. This segmentation allows each region to be optimized for its specific function while using the same underlying structure, resolving the integration complexity issue.
Data Source
AI summary
The present invention provides a structure of a resistor comprising: a substrate having an interfacial layer thereon; a resistor trench formed in the interfacial layer; at least a work function metal layer covering the surface of the resistor trench; at least two metal bulks located at two ends of the resistor trench and adjacent to the work function metal layer; and a filler formed between the two metal bulks inside the resistor trench, wherein the metal bulks are direct in contact with the filler.