Applications > Printed Circuit Boards > Desmear and Etch Back
Desmear and Etch Back
The mechanical drilling of vias in multi-layer PCBs creates a residual resin that smears along the walls of the vias, impeding metalization of the electrical connections. After drilling, resin removal from inner layer posts is required to ensure reliable electrical contact. Traditional methods of etching and desmearing are often not effective for today’s multi-layer board designs due to the capillary effect present with wet chemicals, and the limitations related to the use of advanced board materials. In contrast, plasma effectively removes epoxies, polyimides, high Tg blends, mixed materials, and other resins in standard and high aspect ratio panels.
The figure below illustrate the effect of a plasma desmear process. As displaying in the photograph on the left the copper inner layers within the via are not completely exposed due to drill smear. The photograph on the right displays the exposed copper inner layers after the plasma desmear process.
The figures below illustrate the effect of a plasma etch back process. The figure on the left displays copper layers that are even with the epoxy. After the plasma process the epoxy is etch back exposing more copper for the plating process (middle picture). The picture on the right shows the three-point contact after the plating process. The etch back process improves the reliability of the printed circuit board.
Related Technical Papers:
Related Products:
FP64 Plasma Treatment System
FP64 systems are specifically configured to meet PCB flex panel production requirements.
PROVIA™ Plasma Treatment System
The PROVIA™ System is specifically configured to meet the demands of today’s PCB Manufacturing Operations.
PCB Series Plasma Treatment Systems
PCB series are robust, flexible plasma systems that meet the rigorous demands of 24-hour operation in any PCB manufacturing environment.
VSS Vacuum Storage System
Vacuum Storage Systems. Commercial or Mil-Spec PCB manufacturers benefit from vacuum prepreg stabilizing and conditioning.
PCB Applications Team
James Getty, PCB Market Manager
Getty leads March’s Applications Engineering and Business Development activities, including the Marketing activities supporting the business’ Semiconductor, Printed Circuit Board, and Life Sciences market segments. Getty joined March in 2000. Prior to March Getty has held positions in the semiconductor industry. Getty has a BS, Chemistry from the University of California at Irvine and a PhD in Physical Chemistry from the University of California at Davis.
Lou Fierro, Applications Development Manager, PCB
Lou Fierro joined March Plasma Systems in 1997. Prior to coming to March he spent more than 23 years in engineering, building rigid, flex and exotic printed circuit boards. He now manages applications and contract service at March Plasma Systems Florida facility. Lou is also responsible for process development and technical support.
Ask the Experts
Semiconductor
The Semiconductor Business Group focuses on plasma processes for advanced semiconductor packaging and assembly (ASPA), wafer level packaging (WLP), microelectromechanical systems (MEMS), data storage devices such as thin film read-write heads (TFH) for hard disk drives, and images sensors. More>>>
Medical Device
The Medical Device Business Group is engaged in providing enhanced product performance, more reliable devices and lower cost processes to companies who manufacture leading edge medical devices including cardiac rhythm management products, catheters, stents, ocular devices, and filter media.
More>>>
Printed Circuit Board
Printed circuit board manufacturers work with our PCB Business Group due to the implementation of new materials technology, and smaller geometries in HDI, flex, and rigid flex applications. More>>>