Multi-Spacer Gate Structure for DRAM Doping Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The challenge in semiconductor manufacturing is to reduce the size of DRAM memory cell area and peripheral regions while maintaining the electrical properties of the semiconductor device, particularly in forming spacers and doped regions, as existing methods struggle to properly form heavily doped regions due to proportional reduction in spacer thickness.
Innovation Solution
The method involves forming spacers through multiple cycles of depositing and patterning dielectric layers, allowing for the definition of lightly doped regions and ensuring proper formation of heavily doped regions within the substrate by controlling spacer dimensions, which is achieved by using at least two cycles of dielectric layer deposition and etching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If spacer thickness is reduced proportionally with device miniaturization, then memory cell area is reduced, but heavily doped regions cannot be properly formed
Solution Approach 1:
The spacer formation process is segmented into multiple cycles, with each cycle forming a portion of the final spacer structure. This allows the total spacer thickness to be built incrementally, ensuring that even though the final spacer is thin, the doping process can still achieve proper heavily doped region formation by controlling the timing and conditions of dopant introduction during the multi-cycle process.
2Manufacturing precision
If multiple cycles of dielectric layer deposition and etching are used, then spacer dimension control is improved, but manufacturing process complexity increases
Solution Approach 1:
The spacer structure is formed through nested cycles of deposition and etching, where each cycle builds upon the previous one. The dielectric layers are deposited and patterned in a nested sequence, with each cycle contributing a specific portion of the final spacer structure. This nested approach allows for precise dimensional control while organizing the complex manufacturing process into repeatable, modular units.
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 effectively reduces the size of spacer structures and ensures the proper formation of doped regions, enhancing the electrical properties of the semiconductor device by maintaining the required dimensions and profiles of the spacer structures.
Implementation Method 1
a first dielectric layer is formed on the gate electrode and the substrate
Implementation Method 2
The first spacer includes dopants
Data Source
AI summary
A semiconductor device and a method for preparing the same are provided. The semiconductor device includes a substrate, a gate electrode, a first spacer, and a second spacer. The gate electrode is disposed on the substrate. The first spacer is disposed on a sidewall of the gate electrode. The second spacer covers the first spacer. The first spacer includes dopants.