Search Go
Printed Circuit Board

Desmear & Etch Back

Plasma effectively removes the residual resin and other contaminants in multi-layer printed circuit boards to vastly improve reliability.

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 figures 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.

Photo 1 (before desmear process): copper inner layers of PCB are not completely exposed due to drill smear; Photo 2 (after desmear process): copper inner layers are distinct and exposed

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.

Photo 1 (before etch back process): copper layers are even with epoxy; Photo 2 (after etch back process): increased copper exposure for the plating process; Photo 3 (after plating process): 3-point contact of copper layers and overall increased PCB reliability

Related Products

ProVIA Plasma Treatment SystemProVIA Plasma Treatment System

Nordson MARCH’s ProVIA System is specifically configured to meet the demands of today’s high throughput PCB manufacturing operations for HDI, flexible and rigid circuit board manufacturing.

MaxVIA Plasma Treatment SystemMaxVIA Plasma Treatment System

The MaxVIA™ PCB Plasma Treatment System is designed for high-throughput processing of HDI, Flex, and Rigid Panels for the Printed Circuit Board industry

RollVIA Plasma Treatment SystemRollVIA Plasma Treatment System

Nordson MARCH's RollVIA is a completely self-contained vacuum plasma system with integrated roll-to-roll material handling for production PCB manufacturing environments.

FlexVIA Plasma Treatment SystemFlexVIA Plasma Treatment System

The FlexVIA™ Plasma System from Nordson MARCH is a self-contained vacuum plasma system specifically designed for maximum efficiency and cost effective treatment of flexible materials.

Social Media

Like us on Facebook
Follow us on LinkedIn
Watch us on YouTube