Curved Chuck Contortion for SOI Wafer Cleavage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing smart-cut processes for forming semiconductor-on-insulator (SOI) constructions are costly due to high hydrogen usage and result in rough surfaces, requiring extensive chemical-mechanical polishing (CMP), which reduces throughput and increases costs.
Innovation Solution
A new smart-cut-type process utilizing a curved chuck to contort the wafer and enhance breakage along the damage region, allowing for reduced hydrogen dosage and potentially eliminating or minimizing CMP steps by forming smoother surfaces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high hydrogen dosage is utilized in forming damage regions, then reliable cleavage along the damage region is achieved, but manufacturing cost increases due to high material consumption
Solution Approach 1:
The patent changes the physical state and delivery method of hydrogen from gas phase to plasma phase, and controls the implantation energy and dosage parameters to achieve effective damage region formation with reduced hydrogen consumption. The plasma state enables more efficient hydrogen incorporation into the silicon lattice at lower dosages.
Solution Approach 2:
The patent utilizes phase transition of hydrogen from gas to plasma state before implantation. This phase transition enables the hydrogen to be delivered in a highly reactive state that achieves the same damage region formation effect with lower dosage, thereby reducing material consumption while maintaining cleavage reliability.
2Manufacturing precision
If conventional thermal treatment is used to split the wafer, then cleavage is achieved, but surface roughness increases requiring extensive CMP
Solution Approach 1:
The patent replaces the conventional thermal treatment process with a mechanical contortion process using a curved chuck. The chuck applies mechanical force to induce cleavage along the damage region at room temperature, eliminating the need for high-temperature thermal treatment. This substitution achieves both smooth surfaces (reducing CMP requirements) and maintains processing efficiency.
Solution Approach 2:
The patent employs a curved chuck with a specific radius of curvature to apply distributed mechanical force across the wafer surface. The curvature enables uniform contortion and stress distribution, promoting clean cleavage along the damage region while maintaining surface integrity and minimizing roughness.
3Manufacturing precision
If extensive CMP is performed to reduce surface roughness, then surface quality is improved, but processing time increases and throughput decreases
Solution Approach 1:
The patent performs preliminary action by forming a smooth cleavage surface during the mechanical contortion and breakage process itself. The curved chuck induces controlled fracture that naturally produces a relatively smooth surface, eliminating or reducing the need for subsequent CMP processing. This preliminary surface preparation saves significant processing time.
4Reliability
If high hydrogen dosage is used to ensure complete damage region formation, then cleavage reliability improves, but processing cost increases
Solution Approach 1:
The patent changes the hydrogen delivery parameters from high dosage gas phase implantation to controlled plasma phase implantation with optimized energy and dosage. This parameter change achieves complete and reliable damage region formation at lower hydrogen consumption, reducing material costs while ensuring cleavage completeness.
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 reduces hydrogen usage and surface roughness, thereby decreasing costs and increasing throughput, while enabling the formation of semiconductor-on-insulator constructions with reduced or eliminated CMP requirements.
Implementation Method 1
implantation of hydrogen ions into the wafer to form a damage region
Implementation Method 2
The wafer is bonded to a handle component (which can be a second semiconductor wafer) by hydrophilic bonding through the silicon oxide
Implementation Method 3
The damage region is then thermally treated with a two-phase process. The two-phase process comprises first heating the damage region to a temperature of from about 400° C. to about 600° C. to split the wafer along the damage region
Implementation Method 4
A method of processing a unit comprising crystalline material includes bending the unit with a chuck to induce cleavage along the damage region
Data Source
AI summary
Some embodiments include methods of processing a unit containing crystalline material. A damage region may be formed within the crystalline material, and a portion of the unit may be above the damage region. A chuck may be used to bend the unit and thereby induce cleavage along the damage region to form a structure from the portion of the unit above the damage region. Some embodiments include methods of forming semiconductor-on-insulator constructions. A unit may be formed to have dielectric material over monocrystalline semiconductor material. A damage region may be formed within the monocrystalline semiconductor material, and a portion of the monocrystalline semiconductor material may be between the damage region and the dielectric material. The unit may be incorporated into an assembly with a handle component, and a chuck may be used to contort the assembly and thereby induce cleavage along the damage region.