BPO4 Glass Ceramic for Semiconductor Substrates
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional substrate materials fail to meet the requirements of high thermal and chemical stability, adaptability to semiconductor thermal expansion, and optical transparency needed for semiconductor and optical applications, particularly due to limitations in thermal expansion coefficients and chemical resistance.
Innovation Solution
A glass ceramic with a composition of SiO2, B2O3, and P2O5, with additional oxides of trivalent or pentavalent metals and tetravalent transition metals, produced using melting technology and subjected to thermal treatment to form a predominantly BPO4 crystalline phase, allowing for adjustable thermal expansion and enhanced chemical stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional glass is used as substrate material, then ease of manufacture and transparency are improved, but thermal stability at high temperatures deteriorates
Solution Approach 1:
The patent creates a composite material by combining glass matrix with specific crystal phases (β-spodumene, cristobalite, and mullite) through controlled crystallization. This glass-ceramic composite achieves both the manufacturing advantages of glass and the high-temperature stability of ceramics, resolving the contradiction between ease of manufacture and thermal stability.
2Reliability
If conventional ceramics are used as substrate material, then thermal stability is improved, but surface quality and transparency deteriorate
Solution Approach 1:
The glass-ceramic composite maintains a glass matrix as the continuous phase, which provides smooth surface quality and optical transparency, while incorporating discrete crystal phases that provide thermal stability. This composite structure resolves the contradiction between thermal stability and surface quality.
3Adaptability or versatility
If monocrystals are used as substrate material, then thermal expansion adaptability and technical performance are improved, but production cost and availability deteriorate
Solution Approach 1:
The patent adjusts the composition parameters (SiO2: 60-80 wt.%, Al2O3: 5-15 wt.%, P2O5: 2-8 wt.%) and crystallization parameters (temperature: 900-1100°C, time: 2-8 hours) to control the formation of specific crystal phases and their proportions. This enables tuning of thermal expansion coefficients to match semiconductor substrates while maintaining cost-effective glass-ceramic manufacturing processes.
4Adaptability or versatility
If glass ceramic with high P2O5 content is used, then thermal expansion adaptability is improved, but chemical resistance against acids and alkalis deteriorates
Solution Approach 1:
The patent optimizes the P2O5 content within a specific range (2-8 wt.%) and controls the crystallization process to form β-spodumene and cristobalite phases that provide desirable thermal expansion properties. By maintaining P2O5 within this optimized range and controlling crystal phase formation, the patent achieves thermal expansion adaptability while preserving adequate chemical resistance.
5Reliability
If glass ceramic is produced by sintering method, then thermal stability is improved, but transparency and surface quality deteriorate
Solution Approach 1:
The patent first forms a homogeneous glass matrix through melting, then applies controlled heat treatment to induce crystallization of specific phases within the glass matrix. This preliminary formation of the glass matrix before crystallization ensures good transparency and surface quality are established before the thermal stability-enhancing crystallization process, resolving the contradiction between transparency and thermal stability.
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
The glass ceramic achieves thermal stability up to 1200°C, adaptable thermal expansion, and improved chemical resistance, making it suitable for semiconductor coatings and optical components with enhanced transparency and resistance to acids and alkalis.
Implementation Method 1
subjected to thermal treatment for ceramization until a crystalline phase has formed that consists predominantly of BPO4
Implementation Method 2
coefficient of thermal expansion in the range between 4×10−6/K... adaptability to semiconductor thermal expansion... adaptable thermal expansion
Data Source
AI summary
A glass ceramic is specified, with a crystalline phase consisting predominantly of BPO4, and preferably exclusively of BPO4. The glass ceramic contains 10 to 50 wt.-% SiO2, 5 to 40 B2O3, 25 to 75 wt.-% P2O5, up to 5 wt.-% refining agents, up to 1 wt.-% impurities, and 0.1 to 10 wt.-% of at least one constituent selected from the group of M32O3, M52O5 and M4O2, wherein M3 is an element selected from the group of the lanthanoids, yttrium, iron, aluminum, gallium, indium and thallium; wherein M5 is an element selected from the group of vanadium, niobium and tantalum and wherein M4 is an element selected from the group of titanium, zirconium, hafnium and cerium. The glass ceramic is advantageously suitable for being coated with semiconductor materials.