SEMICONDUCTOR MATERIAL DESIGN

Our semiconductor material design engineers use specific software modules that provide dedicated tools for the analysis of semiconductor device operation at the fundamental physics level. Such modules are based on the drift-diffusion equations, using isothermal or nonisothermal transport models. Such software tools are useful for simulating a range of practical devices, including bipolar transistors (BJTs), metal-semiconductor field-effect transistors (MESFETs), metal-oxide-semiconductor field-effect transistors (MOSFETs), insulated-gate bipolar transistors (IGBTs), Schottky diodes, and P-N junctions. Multiphysics effects play important roles in semiconductor device performance. With such powerful software tools, we can easily create models involving multiple physical effects. For example, thermal effects within a power device can be simulated using a heat transfer physics interface. Optical transitions can be incorporated to simulate a range of devices such as solar cells, light-emitting diodes (LEDs), and photodiodes (PDs). Our semiconductor software is used for modeling semiconductor devices with length scales of 100’s of nm or more. Within the software, there is a number of physics interfaces – tools for receiving model inputs to describe a set of physical equations and boundary conditions, such as interfaces for modeling the transport of electrons and holes in semiconductor devices, their electrostatic behavior…etc. The semiconductor interface solves Poisson’s equation in conjunction with the continuity equations for both the electron and hole charge carrier concentrations explicitly. We can choose solving a model with the finite volume method or the finite element method. The interface includes material models for semiconducting and insulating materials, in addition to boundary conditions for ohmic contacts, Schottky contacts, gates, and a wide range of electrostatic boundary conditions. Features within the interface describe the mobility property as it is limited by the scattering of carriers within the material. The software tool includes several predefined mobility models and the option to create custom, user-defined mobility models. Both these types of models can be combined in arbitrary ways. Each mobility model defines an output electron and hole mobility. The output mobility can be used as an input to other mobility models, while equations can be used to combine mobilities. The interface also contains features to add Auger, Direct, and Shockley-Read Hall recombination to a semiconducting domain, or allows specifying our own recombination rate. Doping distribution needs to be specified for the modeling of semiconductor devices. Our software tool provides a doping model feature to do this. Constant as well as doping profiles defined by us can be specified, or an approximate Gaussian doping profile can be used. We can import data from external sources too. Our software tool offers enhanced Electrostatics capabilities. Material database exists with properties for several materials.

 

PROCESS TCAD and DEVICE TCAD

Technology Computer-Aided Design (TCAD) refers to the use of computer simulations of developing and optimizing semiconductor processing technologies and devices. The modeling of the fabrication is termed Process TCAD, while the modeling of the device operation is termed Device TCAD. The TCAD process and device simulation tools support a broad range of applications such as CMOS, power, memory, image sensors, solar cells, and analog/RF devices. As an example, if you are considering to develop highly efficient complex solar cells, considering a commercial TCAD tool can save you development time and reduce the number of expensive trial fabrication runs. TCAD provides insight into the fundamental physical phenomena that ultimately impact performance and yield. However, using TCAD requires purchasing and licensing the software tools, time for learning the TCAD tool, and even more becoming professional and fluent with the tool. This can be really costly and difficult if you will not be using this software on an ongoing or long term basis. In these cases we can help you offering the service of our engineers who use these tools on an everyday basis. Contact us for more information.

 

SEMICONDUCTOR PROCESS DESIGN

There are numerous types of equipment and processes used in the semiconductor industry. It is not easy nor a good idea to always consider buying a turn-key system offered in the market. Depending on the application and materials considered, semiconductor capital equipment needs to be carefully chosen and integrated in a production line. Highly specialized and experienced engineers are needed to build a production line for a semiconductor device manufacturer. Our exceptional process engineers can help you by designing a prototyping or mass production line that fits your budget. We can help you choose the most suitable processes and equipment that meets your expectations. We will explain you the advantages of particular equipment and assist you throughout the phases of establishing your prototyping or mass production line. We can train you on the know-how and make you ready to operate your line. It all depends on your needs. We can formulate the best solution on a case by case basis. Some major types of equipment used in semiconductor device manufacturing are photolithographic tools, deposition systems, etching systems, various test and characterization tools……etc. Most of these tools are serious investments and corporations cannot tolerate wrong decisions, especially fabs where even a few hours of downtime can be devastating. One of the challenges many facilities may be facing is to make sure their plant infrastructure is made suitable to accommodate the semiconductor process equipment. Much needs to be reviewed carefully prior to making a firm decision on installing a particular equipment or cluster tool, including the current level of the clean room, upgrading of the clean room if needed, planning of the power and precursor gas lines, ergonomy, safety, operational optimization….etc. Speak to us first before getting into these investments. Having your plans and projects reviewed by our seasoned semiconductor fab engineers and managers will only positively contribute to your business endeavors.

 

TESTING OF SEMICONDUCTOR MATERIALS AND DEVICES

Similar to the semiconductor processing technologies, the testing and QC of semiconductor materials and devices requires highly specialized equipment and engineering know-how. We serve our clients in this area by providing expert guidance and consulting on the type of test and metrology equipment that is the best and most economic for a particular application, determining and verifying the suitability of the infrastructure at customer’s facility…..etc. The clean room contamination levels, vibrations on the floor, air circulation directions, movement of people,….etc. all need to be carefully assessed and evaluated. We can also independently test your samples, provide detailed analysis, determine root cause of failure…etc. as an outside contract service provider. From prototype testing to full scale production, we can help you ensure the purity of starting materials, we can help reduce development time and solve yield problems in the semiconductor manufacturing environment.

 

Our semiconductor engineers use the following software and simulation tools for semiconductor process and device design:

• ANSYS RedHawk / Q3D Extractor / Totem / PowerArtist

• MicroTec SiDif / SemSim / SibGraf

• COMSOL Semiconductor Module

 

We have access to a wide range of advanced lab equipment to develop and test semiconductor materials and devices, including:

• Secondary Ion Mass Spectrometry (SIMS), Time of Flight SIMS (TOF-SIMS)

• Transmission Electron Microscopy – Scanning Transmission Electron Microscopy (TEM-STEM)

• Scanning Electron Microscopy (SEM)

• X-Ray Photoelectron Spectroscopy – Electron Spectroscopy for Chemical analysis (XPS-ESCA)

• Gel Permeation Chromatography (GPC)

• High Performance Liquid Chromatography (HPLC)

• Gas Chromatography – Mass Spectrometry (GC-MS)

• Inductively Coupled Plasma Mass Spectrometry (ICP-MS)

• Glow Discharge Mass Spectrometry (GDMS)

• Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS)

• Liquid Chromatography Mass Spectrometry (LC-MS)

• Auger Electron Spectroscopy (AES)

• Energy Dispersive Spectroscopy (EDS)

• Fourier Transform Infrared Spectroscopy (FTIR)

• Electron Energy Loss Spectroscopy (EELS)

• Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES)

• Raman

• X-Ray Diffraction (XRD)

• X-Ray Fluorescence (XRF)

• Atomic Force Microscopy (AFM)

• Dual Beam - Focused Ion Beam (Dual Beam – FIB)

• Electron Backscatter Diffraction (EBSD)

• Optical Profilometry

• Residual Gas Analysis (RGA) & Internal Water Vapor Content

• Instrumental Gas Analysis (IGA)

• Rutherford Backscattering Spectrometry (RBS)

• Total Reflection X-Ray Fluorescence (TXRF)

• Specular X-Ray Reflectivity (XRR)

• Dynamic Mechanical Analysis (DMA)

• Destructive Physical Analysis (DPA) compliant with MIL-STD requirements

• Differential Scanning Calorimetry (DSC)

• Thermogravimetric Analysis (TGA)

• Thermomechanical Analysis (TMA)

• Real Time X-Ray (RTX)

• Scanning Acoustic Microscopy (SAM)

• Tests to evaluate electronic properties

• Physical & Mechanical Tests

• Other Thermal Tests As Needed

• Environmental Chambers, Aging Tests

 

Some of the common tests we perform on semiconductors and devices made thereof are:

• Evaluating the cleaning efficacy by quantifying surface metals on semiconductor wafers

• Identifying and locating trace level impurities and particle contamination in semiconductor devices

• Measurement of the thickness, density, and composition of thin films

• Characterization of dopant dose and profile shape, quantifying bulk dopants and impurities

• Examination of the cross-sectional structure of ICs

• Two-dimensional mapping of matrix elements in a semiconductor microdevice by Scanning Transmission Electron Microscopy-Electron Energy Loss Spectroscopy (STEM-EELS)

• Identification of contamination at interfaces using Auger Electron Spectroscopy (FE-AES)

• Visualizing and quantitative evaluation of surface morphology

• Identifying wafer haze and discoloration

• ATE engineering and testing for production and development

• Testing of semiconductor product, burn-in and reliability qualification to assure IC fitness