Laser direct imaging, LDI

The RCC approach suffers from misregistration of window opening to capture pad when the surface and capture pad diameter becomes less than 250 pm, which causes serious defects (see Fig. 22.22). Laser via process practitioners have several solutions to this problem.They can use liquid resin or resort to a Yag or Yag/CO2 laser. Since a Yag laser can break through copper foil, the beam can be directed to the capture pad position accurately. Another choice is to use laser direct imaging (LDI) for window etching in order to benefit from the speed of the CO2 laser. 

In the past, several photoresists were formulated for exposme at a visible wavelength,450 nm, using specialized exposure equipment—either visible lasers or magnified projection printing. More recently, laser direct imaging (LDI) based on the Ar+ laser ontpnt clnstered aronnd 360 nm has been commercialized. Conventional photoresists can be exposed on LDI eqnipment, bnt higher photospeed has been key to the productivity and economics of LDI. 

LDI laser direct image LOM laminated object manufacturing... 

Laser direct imaging equipment (LDI) is capable of making the dimensional corrections for the serious distortions of the unstable flexible materials promptly. It provides a high productivity for the prototype or middle volume productions. On the other hand, it is not very capable for traces finer than 25 microns lines and spaces. Lower throughput compared to traditional exposure machines, especially for double-side imaging, is the barrier for the volume productions. 

MALDI-IMS is still limited to about 20 pm spatial resolution (with 10-50 pm the most commonly achievable spatial resolution at this time), typically obtained with commercial ion sources (80). Recently, Zavalin et al. demonstrated that 5 pm spatial resolution can be achieved for MALDI-IMS instruments by spatial filtration of the laser beam by using a 25 pm ceramic pinhole filter (81). Secondary ion mass spectrometry (SIMS), developed in the 1960s (82), offers a complementary or alternative method to MALDI-IMS and other matrix-free LDI-MS methods for the acquisition of higher spatial resolution images. In SIMS, a focused high-energy primary ion beam (such as Cs+, Au3+, Bi5+, or C60+) is used to directly bombard the sample... 

---