The key technology system for achieving nanoscale precision in semiconductor components covers three dimensions: material control, process optimization, and detection verification:
1、 Material preparation and pretreatment
Wafer thinning control
The original thickness of a 12 inch wafer is 775 μ m, and thinning requires the use of temporary bonding/debonding technology to achieve ultra-thin processing below 20 μ m, with thickness variation controlled within<1 μ m.
SiC substrate requirements: Si surface roughness Ra ≤ 0.3nm, C surface Ra ≤ 0.5nm, using a combination of mechanical initial polishing and chemical mechanical precision polishing process.
Material stability optimization
Perform aging treatment (150 ℃ × 4h) on easily deformable materials such as stainless steel to release internal stress.
The processing environment temperature is stable at 23 ± 2 ℃, and the temperature fluctuation in the constant temperature chamber is ≤ 1 ℃.
2、 Core processing technology
1. Ultra precision surface treatment
Chemical mechanical polishing (CMP):
Through the synergistic effect of chemical corrosion (customized polishing solution) and mechanical grinding (nano SiO ₂/CeO ₂ abrasive particles), atomic level flatness with surface roughness<0.1nm is achieved.
Polishing parameter control: pressure 0.5-7psi, speed 30-120rpm, polishing solution pH 9-11 (adjusted according to material).
Laser assisted processing:
Difficult to cut materials such as titanium alloys are locally preheated using a 500W laser, reducing cutting force by 40% and improving roughness by 50%.
3、 Thermal deformation and stress control
Thermal management technology
Using micro lubrication (MQL) technology, the cutting temperature rise is controlled within 15 ℃.
Machine tool thermal deformation dynamic compensation system, with an accuracy of ± 0.003mm/m.
Stress relief process
Optimize cutting parameters: reduce the feed rate to 0.05mm/r and gradually process in three stages: coarse, medium, and fine (with a margin of 0.2mm → 0.05mm → 0.01mm).
Pulse cooling technology: water pressure of 20MPa, interval of 0.5s, to reduce thermal stress accumulation.
4、 Full process accuracy verification
1. Online monitoring system
Multi sensor fusion: Laser displacement sensor (± 1 μ m) combined with vibration sensor (10kHz sampling rate), real-time correction of machining path.
Tool status monitoring: Automatically adjust parameters when acoustic emission signal>5dB to prevent chip buildup.
2. Ultimate testing standards
Surface quality: roughness Ra<0.1nm after CMP (verified by atomic force microscopy).
Dimensional tolerance: Critical dimension CPK ≥ 1.67, three-dimensional sampling ≥ 12 points/feature.
Functional verification:
The moving parts have passed 10 ⁵ fatigue tests (120% rated load).
The helium leak detection rate of the seal is ≤ 1 × 10 ⁻⁶ mbar · L/s.
5、 Cutting edge technology in the industry
Composite machining center: The turning and milling composite equipment integrates RTCP function, reducing clamping errors and achieving a position accuracy of ± 0.003mm.
Intelligent closed-loop control: Real time feedback of online detection data to the processing system, dynamically correcting process parameters.
Sumitech establishes a process window database and determines the optimal parameter combination through DOE experiments; Industrial CT scanning (resolution ≤ 5 μ m) is needed to verify internal defects in the medical/aviation field. For cutting-edge applications such as 3D packaging, it is necessary to simultaneously optimize the temporary bonding strength and the stability of ultra-thin wafer transfer.
If you have any parts that need to be processed, please feel free to email us for consultation. We will provide processing solutions and process explanations.
