On-Chip Resistor TCR Tuning via Seebeck Terminals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing on-chip resistor technologies face challenges in accurately controlling the temperature coefficient of resistance (TCR) due to variations in resistivity with temperature, which affects their performance in integrated circuits.
Innovation Solution
The implementation of a dual-resistor body structure with overlapping Seebeck terminals, where the TCR is adjusted based on the Seebeck coefficient of these terminals, allowing for independent control of the TCR through doping levels and conductivity types, thereby stabilizing resistance across temperature changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If traditional single resistor body structure is used, then fabrication is simpler, but TCR control precision is insufficient
Solution Approach 1:
The resistor body is divided into multiple segments (first resistor body and second resistor body) with different TCR characteristics. Each segment can be independently designed and fabricated with specific doping levels and geometries to achieve different resistance values and TCR values, allowing precise control of the overall TCR through combination of segments.
Solution Approach 2:
The patent uses composite resistor structures combining different resistor materials (e.g., polysilicon with different doping levels, or different semiconductor materials) to create resistor bodies with different TCR characteristics. This allows the overall TCR to be tuned by adjusting the proportion and arrangement of different material components.
2Manufacturing precision
If TCR is adjusted through material properties alone, then fabrication process is simpler, but TCR tuning range and precision are limited
Solution Approach 1:
Different regions of the resistor structure are assigned different local properties: the first resistor body has specific doping concentration and geometry for base resistance, while the second resistor body has different doping concentration or geometry for TCR adjustment. The Seebeck terminals are positioned at specific locations to maximize thermal gradient effects for TCR control.
Solution Approach 2:
The patent employs multiple adjustable parameters including doping concentration, resistor body length, width, thickness, and Seebeck terminal positioning to independently control both resistance value and TCR. By changing these geometric and material parameters, precise TCR tuning over a wide range is achieved without requiring complex additional fabrication steps.
3Manufacturing precision
If resistor material thickness is increased to reduce resistance, then resistance value decreases, but TCR control capability is reduced
Solution Approach 1:
Instead of using a single thick resistor layer, the structure segments the resistance function across multiple layers or regions with different thicknesses. The first and second resistor bodies can have different thicknesses, allowing one to provide base resistance while the other provides TCR control, thus maintaining TCR control capability while achieving low resistance values.
Solution Approach 2:
The patent transitions from controlling resistance solely through thickness (one dimension) to utilizing planar dimensions (length, width) and vertical stacking of multiple resistor bodies with different properties. This dimensional expansion allows independent optimization of resistance value and TCR without being constrained by thickness alone.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables precise tuning of the TCR to zero, positive, or negative values, maintaining consistent resistance with temperature fluctuations, enhancing signal transfer and operational stability by rebalancing currents through Seebeck feedback loops.
Implementation Method 1
a first Seebeck terminal arranged to overlap with the first resistor body and the second resistor body, and a second Seebeck terminal arranged to overlap with the first resistor body and the second resistor body. The second Seebeck terminal has a spaced relationship with the first Seebeck terminal along a length of the first resistor body and the second resistor body. The temperature coefficient of resistance of the on-chip resistor is based at least in part on a Seebeck coefficient of first and second Seebeck terminals.
Implementation Method 2
During operation, the temperature of an on-chip resistor changes due to Joule heating.
Data Source
AI summary
Device structures and fabrication methods for an on-chip resistor. A first Seebeck terminal is arranged to overlap with first and second resistor bodies of the on-chip resistor. A second Seebeck terminal is also arranged to overlap with the first and second resistor bodies. The second Seebeck terminal has a spaced relationship with the first Seebeck terminal along a length of the first and second resistor bodies. The temperature coefficient of resistance of the on-chip resistor is based at least in part on a Seebeck coefficient of first and second Seebeck terminals.