Wafer implantation was discovered as part of the Manhattan Project in the 1940’s. However, today it is most common within the semiconductor industry.
During the wafer implant process, ions are accelerated in an electric field and shot into a beam at a wafer. This method is common because it allows for very precise dosing, which leads to more accurate location and depth of particles on the target wafer. Ion implantation can take place at room temperature, so any other dopants do not diffuse out during the process.
To start, an ion source sends particles in a beam perpendicular to the target wafer (1). As the wafers leave the ion source, a series of magnets remove any excess particles that do not belong (2).
Once the particle beam leaves the ion source, lenses throughout the entire system ensure the beam stays focused on the target wafer (3).
After the ion beam leaves the source and goes through the first magnetic filtration, a process called mass separation uses another magnetic field to turn the particles exactly 90° (4). At this stage, particles filter out if their atomic weight does not exactly match that of the magnetic field. This makes sure to filter out any impure particles.
Next, the particles make their way to the acceleration lane (5). In the acceleration lane, anywhere from 10 to 500 keV (kiloelectron volts), depending on desired depth, accelerates the ion beam to speeds high enough to implant the particles onto the target wafer. Depending on the application, as low as 1 keV and as high as 5 meV (megaelectron volts) accelerate the particles in the ion beam. When at their max velocity, boron particles in an ion beam accelerated to 200 keV can be moving at speeds of up to 2,000,000 m/s.
After the beam makes contact with the wafer (6), only about 5% of ions bond due to the high velocity of the ion beam. The wafer is then annealed so the bonds can be made.
SVM Wafer Implant Capabilities:
- Diameters: 25mm to 300mm
- Low, medium and high dose implant solutions.
- Implant energy range: 1KeV to 3,000KeV.
- Will provide implant on both bare and patterned wafer substrates.
- Will accept small volume prototype and large volume production quantities.
Please CONTACT SVM today for more information on wafer implanting, to request a quote or to discuss your current requirements.