Specific Applications of White Fused Alumina in Semiconductor Industry
White fused alumina also named white aluminum oxide,white corundum ,white electrocorundum or white fused aluminum oxide etc
Important Note: High-purity, low-sodium white fused alumina is used exclusively in the double-sided lapping (thinning) process following substrate slicing; it is not used for the final CMP (Chemical Mechanical Polishing) mirror-finish polishing of wafers. Its specific applications include:
- Double-sided free-abrasive lapping of silicon (Si) or silicon carbide (SiC) substrates
Process stage: Single-crystal slicing → Double-sided lapping (using a water-based slurry containing white fused alumina→ Single-sided polishing/CMP.
Function: To remove saw marks and subsurface damage layers left by wire-saw cutting; to control the Total Thickness Variation (TTV) and flatness of the wafer while thinning the substrate to the target thickness; and to reduce surface roughness, serving as a preparatory step for subsequent mirror-finish polishing.
Recommended particle sizes for white fused alumina (WA) micropowder: F800, F1000, F1200, F1500, F2000 (or JIS-series micropowders: #800 #1000 #1200 #1500 #2000 #2500 #3000 #4000).
Process setup: In a double-sided lapping machine, wafers are placed within SiC retainer rings. The high-purity, low-sodium white fused alumina micropowder is suspended in a slurry, facilitating a free-abrasive lapping process between cast-iron lapping plates. Material requirements: High purity, low sodium, low iron, and low magnetic impurity content; strict control over mobile ions to prevent device leakage failures.
- Lapping Plate (Cast Iron/Copper) Conditioning
Application: During long-term use, the grooves on cast iron or copper lapping plates (used in double-sided lapping machines) can become dull. High-purity, low-sodium white fused alumina—or abrasive stones made from such powder—is used to recondition the plate surface. This restores the groove profile, ensuring a stable material removal rate and controllable Total Thickness Variation (TTV) for wafers.
Recommended grit sizes for high-purity, low-sodium white fused alumina (WA) micropowder: F600, F800, and F1000. The low iron and sodium content prevents contamination of copper plate surfaces.
- Precision Lapping of Semiconductor Alumina Ceramic Components
Used for the rough, medium, and precision lapping, as well as chamfering and deburring, of 99.6%/99.9% alumina ceramic components—such as vacuum chucks, carriers, insulating parts, and positioning rings—found in semiconductor equipment. High-purity, low-sodium white fused alumina (WA) micropowder is chemically inert, minimizing the risk of metal ion leaching that could contaminate the ceramic components.
- Micro-blasting of Semiconductor Quartz Components
Used for the matte-finish blasting of quartz components—such as bell jars, rings, and carriers—found in diffusion furnaces and etching equipment. High-purity, low-sodium white fused alumina (WA) micropowder is selected to:
Achieve a uniform and controllable surface roughness (Ra), which enhances thin-film adhesion, and to eliminate surface defects on the quartz.
The abrasive particles are preferably equiaxed (isometric) in shape; following the blasting process, the components undergo ultrasonic cleaning to ensure that no abrasive particles remain embedded within the quartz substrate. 5. Use of High-Purity, Low-Sodium white Fused Alumina in Bonded Abrasives and Lapping Pastes
High-purity, low-sodium white fused alumina is used to manufacture sharpening stones, abrasive sticks, and lapping pastes. These products are employed for the precision grinding and chamfering of semiconductor ceramic components and jigs in small-batch production.
Zhengzhou Haixu Abrasives Co., Ltd. produces and supplies high-purity, low-sodium white fused alumina in the following grit sizes:
FEPA: F230, F240, F280, F320, F360, F400, F500, F600, F800, F1000, F1200, F1500, F2000
JIS: #240, #280, #320, #360, #400, #500, #600, #700, #800, #1000, #1200, #1500, #2000, #2500, #3000, #4000, #6000, #8000
Chemical composition analysis report of high-purity, low-sodium white fused alumina produced by Zhengzhou Haixu Abrasives Co., Ltd.
