Wafer CleaningIn the front - end semiconductor process, metal ions, polishing particles (such as cerium oxide), and organic substances remaining on the wafer surface need to be thoroughly removed. Ultrasonic waves strip off contaminants through the high - frequency cavitation effect (20kHz - 1MHz). After cleaning, the cleanliness of the wafer surface can reach 5 particles (0.3μm)/cm², meeting the requirements of subsequent processes such as lithography and deposition. For example, the cleaning of polysilicon wafers requires a multi - stage process combining deionized water and alkaline solution, and uniform cleaning is achieved through automated operation by a robotic arm.Photoresist Residue RemovalThe photoresist and chemical substances remaining after lithography will affect the subsequent etching accuracy. The ultrasonic cleaning machine, in combination with an ammonia/hydrogen peroxide mixture (SC - 1) or ozone water, can decompose and remove nanoscale colloidal residues while avoiding damage to the micro - structure on the wafer surface. A certain case shows that after using 130kHz high - frequency ultrasonic waves, the photoresist removal efficiency is increased by 40%.Packaging and Testing PhasesSolder particles and grease generated during the chip packaging process need to be thoroughly cleaned. The ultrasonic cleaning machine penetrates into the gaps between BGA solder balls through the cavitation effect to remove contaminants and ensure packaging reliability. Cleaning before testing can reduce signal interference and improve the yield rate. The actual measurement of VGT equipment shows that the qualified rate of the electrical performance of the packaged chip is increased from 92% to 99.5%.

As a precision optical component, the surface of a mobile phone lens can be significantly affected in imaging quality by nanoscale stains such as fingerprints, oil films, and dust. Ultrasonic cleaning technology, with its non - contact physical cleaning advantages, has become one of the core processes in the production and maintenance of mobile phone lenses.### I. Technical Principles and Parameter AdaptationUltrasonic cleaning generates cavitation effects in the liquid through high - frequency vibrations (20kHz - 132kHz), forming micron - scale bubble explosions (with a diameter of 10 - 50μm). These can penetrate into slits as narrow as 0.3mm at the edge of the lens, peeling off adhesive contaminants. Compared with traditional wiping, its cleaning efficiency is increased by more than 3 times, and the surface damage rate is reduced by 97%.**Frequency Selection**: The coating layers of mobile phone lenses, such as AR anti - reflection films, are sensitive to mechanical shock. A high - frequency and low - power solution is required. For example, 132kHz high - frequency ultrasonic waves have strong penetration but weak impact force, which is suitable for materials such as lens glass and resin lenses.**Cleaning Solution Preparation**: Neutral water - based cleaning agents (pH 6 - 8) or deionized water should be selected to avoid the corrosion of the coating by strong acid or alkaline solvents. Some manufacturers use pure water + 0.5% bionic enzyme cleaning solution to achieve the combination of biodegradation and efficient decontamination.### II. Standardized Operating Procedures**Pre - treatment Stage**After disassembling the lens module, gently wipe the large - particle stains on the surface with a microfiber cloth to prevent the coating from being scratched by particles during ultrasonic cleaning.**Cleaning Parameter Settings****Time Control**: Set the time from 5 to 15 minutes according to the degree of contamination (for heavy oil stains, 10 minutes) to avoid the over - load of the cavitation effect causing the coating to peel off.**Temperature Adjustment**: The constant - temperature system maintains a temperature of 30 - 45℃. High temperatures accelerate the dissolution of contaminants, but temperatures exceeding 50℃ may cause the resin lens to deform.**Rinsing and Drying**After rinsing with pure water, slow - pull dehydration and circulating hot - air drying technology (80℃2℃) are used to replace the traditional solvent dehydration process, avoiding the formation of water stains due to IPA residues.