• What is a semiconductor

Semiconductor refers to a material with conductivity between that of a conductor and an insulator at room temperature.

Semiconductors can be divided into major categories based on manufacturing technology, such as integrated circuit devices, discrete devices, optoelectronic semiconductors, logic ICs, analog ICs, and storage devices.

• What is a chip

Chip, also known as microcircuit, microchip, integrated circuit (IC). It refers to silicon wafers containing integrated circuits, which are small in size and often part of computers or other electronic devices.

• Manufacturing process flow

Note: CMP stands for Chemical Mechanical Polishing*The image is sourced from the internet

• Lithography and etching

Photolithography is the process of transferring patterns onto photoresist that covers the surface of a semiconductor silicon wafer. These patterns must be transferred to the thin layers that make up the device underneath the photoresist, a process we call etching, which selectively etches off the unmasked parts of the thin layer.

• Etching method

There are two basic methods of etching: wet chemical etching and dry etching.

The mechanism of wet chemical etching mainly includes three stages: reactants diffuse to the surface of reactants, chemical reactions occur on the surface, and then the reaction products are removed from the surface through diffusion. Wet chemical etching is more suitable for surface etching of polycrystalline silicon, oxides, nitrides, metals, and III-V compounds.

Near infrared spectroscopy technology has a wide range of applications in the semiconductor industry due to its advantages.

• Non invasive methods
• Preventing minor pollution
• High accuracy and good reproducibility
• No need to dilute the sample
• Can be quantitatively analyzed
• Can perform both chemical analysis and physical indicators
• An online near-infrared spectrometer with a specially designed fiber optic probe can be integrated into the entire system

► Application Case 1: Determination of mixed acid etching solution using near-infrared spectrometer

The spectra obtained using colorimetric dishes with 1mm and 4mm optical paths are as follows. By observing the spectra, it can be observed that the spectral noise of the colorimetric dish with 4mm optical path starts to increase from 1900nm. Therefore, we chose a 1mm optical path colorimetric dish for measurement.

The content of each component in the mixed acid etching solution modeled and measured by Vision software is shown in the table below, which is consistent with the values analyzed by conventional laboratory methods. It can be seen that the near-infrared prediction results are basically consistent with the laboratory methods, with very small errors.

► Application Case 2: Using an online near-infrared spectrometer to measure cleaning solution

The following figure shows the continuous monitoring of the customer's SC1 cleaning solution status using the Swiss Wantong online near-infrared spectrometer. We can see that as the cleaning solution is consumed, NH₄The content of OH gradually decreases, and customers can operate the cleaning process according to the monitoring situation.

► Application Case Three: Dynamic Monitoring of IPA Isopropanol Using Online Near Infrared Spectrometer

IPA isopropanol, as a cleaning and removal agent, may introduce impurities into the solvent during the cleaning process. Its near-infrared spectrum is shown in the following figure. In the wavelength range of 1900-2000nm, the influence of impurity EKC-265 on the spectrum is clearly visible.

We use this band to establish a near-infrared model of EKC-265, and we can see the R of the model²Reaching 9.9989, SEC is 0.0629. By using this model, we can monitor the changes in impurity content in isopropanol.

Swiss Wantong DS2500Near infrared spectroscopy liquid analyzer and accessories

Swiss Wantong XDSOnline near-infrared spectroscopy analyzer

• Non destructive spectroscopy technology
• The wavelength range is 800-2200nm, which can achieve a wide range of applications
• Can perform real-time qualitative analysis, multi-component quantitative analysis, and trend analysis
• The instrument complies with NEMA4X protection level
• No need for chemical reagents, environmentally friendly and cost saving
• Teflon material circulation pool