Semiconductor Manufacturing

Semiconductor manufacturing involves workflows where integrated circuits (ICs) comprised of components like diodes, resistors, and transistors are created on a semiconductor wafer; the wafers are then cut into individual ICs, packaged, and integrated to manufacture the final product. A semiconductor wafer is made of pure elements, typically silicon. Depending on the application, other elements, such as germanium or materials like gallium arsenide, are also used in wafer fabrication. Wafer manufacturing is a technologically advanced process in which each step requires high precision involving specialized equipment and a clean room environment.

Step 1: Design
Fabless or independent design companies and electronic manufacturers design semiconductor chips. 

Step 2: Front-end manufacturing
Also known as wafer fabrication, it is a crucial step in the semiconductor industry where all the initial stages of creating various individual components of ICs takes place. It starts with slicing a pure silicon ingot into discs/wafers, continues with polishing wafers to a flawless finish, and goes on further to the creation of intricate patterns on the wafer that forms an IC in multiple extensive and advanced steps.

Step 3: Back-end manufacturing 
In back-end manufacturing, the silicon wafers undergo precise cutting to form individual dies/ semiconductor chips, followed by assembly and packaging steps. The packaged chips are tested to ensure they meet specifications for final assembly on printed circuit boards (PCB). PCB manufacturing is closely linked to the packaging step in chip fabrication as the PCBs support and connect the electronic components. The PCB manufacturing process involves steps such as etching, laminating, drilling, electroplating, screen printing, and lithography.

Step 4: End-product integration
Chips are integrated to manufacture the final end-product, like a smartphone or a computer.

Creating defect-free semiconductor chips is crucial to the smooth functioning of products and processes that are essential to everyday life, including private and public services in the global economy. The semiconductor industry strives for:

It is the first step of wafer fabrication, where a silicon ingot is cut to obtain silicon wafers. The wafers undergo several chemical and mechanical processes in foundries and fabs to achieve the needed planarity and quality. They are processed through a series of steps in wafer fabrication, such as photolithography, etching, cleaning, and doping, to create the various components of an IC. A sequence of wet processing steps, such as etching, cleaning, and polishing, involve a variety of specialty chemicals.

A CMP slurry mix contains chemicals as dispersed particles in a liquid phase. Accurate weighing of the individual components of the polishing slurry is critical to avoid damaging wafers and wafer processing equipment. PBK9/PFK9-APW platforms allow weighing up to 3000 kg, offer ease of integration in automated weighing processes, and can be set to compensate for environmental influences that could impact the weighing results. For up to 5000 kg in tank weighing applications, PowerMount™ weigh modules are ideal, as they offer high accuracy, reliability and condition monitoring to give you peace of mind that the system is performing to your expectations. To find the best-suited weighing solution for slurry processes, METTLER TOLEDO suggests the GWP® Recommendation.

During the polishing process, it is essential to monitor the percent of dispersed solids in the slurry blend at various stages to ensure the optimum degree of polishing. This can easily be achieved at high speed by using a moisture analyzer. The Halogen Moisture Analyzer HX204 comes with advanced features that offer ease of use, data and user management, and instant decision-making with customizable control limits. With the integrated method development wizard, it is very easy to develop a robust method to match the result of the reference drying oven procedure in a fraction of the time, resulting in increase in productivity.

Monitoring the pH and conductivity of the CMP slurry is extremely important to maintain a stable colloidal slurry; this can be easily achieved by selecting the right single or multiparameter benchtop pH meter or automated system with data management options and suitable accessories, sensors, and consumables.

Hydrogen Peroxide (H₂O₂) is a commonly used chemical oxidizer in CMP slurry blends. The efficiency of polishing depends on the oxidation process on the silicon wafer. Many techniques, such as titration, can be used to determine the concentration of H₂O₂ in a solution that is used to produce the slurry. Alternatively, density or refractive index measurement offers a fast, simple and safe analysis that can be easily performed with a benchtop density meter and refractometer or portable solution by METTLER TOLEDO. For cost-effective and high-quality wafer yields, the quality of a CMP slurry blend can be controlled before its use in downstream polishing applications by ensuring its density in a predefined range.

In a typical semiconductor fab, thousands of cubic meters of ultrapure water (UPW) are used daily in the cleaning, etching, and rinsing of wafers and substrates. Precise and reliable process analytical measurements are essential for ensuring that UPW is fit for use in chip manufacturing steps and for optimizing water usage to maximize recovery and reuse. Recognized by standards setting groups throughout the world, METTLER TOLEDO Thornton’s UPW monitoring solutions ensure the highest quality of water is being utilized for chip fabrication. Our UniCond™ sensors and 6000TOCi, 2850Si, and 2300Na analyzers can be installed in deionizing water systems to detect any changes in resistivity, TOC, silica, and sodium, with minimal operator intervention.

Wafer weighing in fabs and QC can be challenging as the weighing stations are often close to a wet bench and in a clean room environment. Given the harsh conditions and productivity demands, the weighing solutions must be robust and provide stable measurements at a high weighing speed. METTLER TOLEDO’s XPR Analytical Balances combine a high-performance load cell with active temperature control technology and a SmartGrid weighing pan for fast and accurate weighing. The SmartPan in XPR Precision Balances provides the necessary stability to obtain weighing results up to twice as fast as a standard weighing pan.

Professional accessories, such as ErgoClips for convenient wafer weighing and easy operation, further support efficient workflows in semiconductor manufacturing operations. Connectivity and data management, such as LabX software, help ensure regulatory compliance and data traceability.

Photoresists are light-sensitive materials coated on the chips, which are then partially exposed to light through a patterned mask in a photolithography process to create an IC circuit. Differential Scanning Calorimetry (DSC) is a powerful tool for understanding the physicochemical behavior of the chemically amplified resists (CAR) (a photoresist material) and for optimizing the lithographic process. One single measurement with temperature-modulated DSC (TMDSC) can reveal information about thermal effects associated with the lithographic process, such as vaporization, cross-linking and the glass transition temperature of the photoresist material.

When it comes to sample preparation for DSC measurements of a few milligrams, XPR microbalances are a key asset. With XPR balances, weighing results can be transferred to the STAR^e software with a single click. METTLER TOLEDO offers a complete workflow solution that includes DSC instruments, balances, software, and accessories, as well as extensive application expertise in both micro-weighing and thermal analysis.

Etching solutions and the CMP process during chip fabrication use hydrofluoric acid, leading to high fluoride concentrations in effluents from the semiconductor industry. Precipitation, flocculation, and filtration are often used to remove potential contaminants. Successful precipitation can occur only at an optimum pH range; therefore, the pH of effluent indirectly indicates if the concentration of contaminants is below a certain limit. Alternatively, a direct measurement of ion concentration using Ion Selective Electrodes (ISE), e.g., perfectION™ comb F electrode fluoride ions, can also be used to monitor the wastewater.

This is the assembly and packaging stage, where individual semiconductor chips are cut from the wafer and packaged in a case. In the next step, bonding wires connect the chip to the external circuit. The process also includes testing and final inspection of the ICs according to the standards and regulations.

METTLER TOLEDO’s laboratory software solutions accelerate the processing speed through electronic data collection and powerful data evaluation, aiding the automation of workflows and reducing manual administration by centralizing asset management. Enabling the connectivity of instruments allows for simple and centralized control of the interconnected equipment. Easy retrieval of the data laboratory software supports data integrity needs for internal regulations and external compliance.

LabX™ laboratory software manages your instruments, SOPs, and users. It enables productivity gain through digitalization, electronic data management, and workflow guidance to meet required regulatory standards and data integrity needs through a single software solution. LabX fully networks METTLER TOLEDO balances, titrators, pH meters, UV/Vis spectrophotometers, density- and refractometers, melting point systems, and automation solutions.

STAR^e Excellence Thermal Analysis Software is a powerful platform that connects METTLER TOLEDO’s thermal analysis systems and enables modularity, flexibility, and automation.

iC Software Suite for automated reactors and in-situ analyses integrates the entire experimental workflow in automated synthesis reactor and in-situ analysis, making it simple to visualize process data and interpret and report results in order to gain a real-time, interconnected picture from each experiment and help in decision making in R&D for further optimization of processes and products.

METTLER TOLEDO’s professional services cover the entire lifetime of the product, starting from secure device selection, correct installation, and user training for a perfect start with initial and recurring calibration. They also include verification to ensure the performance and reliability of your equipment, support as you strive to comply with local and global norms and regulations, and preventive maintenance to help minimize risk and extend the lifetime of your equipment.

Explore and choose the right care package for your needs from a wide variety of different service offerings at the time of purchase with ExtendedCare or at a later point with BasicCare, StandardCare, and ComprehensiveCare.

With our Good Measuring Practices offering, we help you find the right instruments for your needs, providing advice and training on how to operate, calibrate, and maintain your instruments effectively.