X-Ray LIGA - X-Ray Lithography - X-Ray Masks
Making the impossible, possible
no stress.no burrs. no problem
Is LIGA a possible solution for you? Let's take a closer look.
If you think LIGA may be a solution for you, we recommend you contact an engineer for an expert evaluation.
X-Ray LIGA and UV LIGA, is a highly specialized additive manufacturing process. While both processes have the ability to produce incredibly small features, and, maintain exceptional accuracy; X-Ray differentiates from UV with the ability to produce tall, vertical structures (see image 1). While both processes offer the ability to produce crisp, clean, burr free features down to (1) micron, these highly specialized process makes the impossible a possibility. LIGA is used throughout leading high tech industries.
What is LIGA?
This image in Figure 1 is an example of microscopic nozzles produced using X-Ray LIGA.
The image was captured with an electron microscope at 200X magnification. The unique capability of X-Ray LIGA offers us the ability to produce tall, vertical structures; which is not capable with UV LIGA. In many aspects, you could think of it in terms of an extremely accurate, micro 3d printing.
High aspect ratios on the order of 100:1
Straight side walls
Smooth side walls suitable for optical mirrors
Structural heights from tens of micrometers to several mm
Structural details over distances of centimeters
Positional and feature accuracy in the range of +/- 1µm.
X-Ray LIGA - An Additive Manufacturing Process
X-Ray Lithography – X-Ray Masks - LIGA
To understand LIGA, one must first understand Electroforming. The (2) fundamental types of LIGA are UV and X-Ray. UV LIGA utilizes a UV light source during exposure while deep X-Ray lithography uses a synchrotron with wavelengths on the order of 0.1 nm and modified procedures such as the LIGA process, to fabricate deep and even three-dimensional structures
The more common type of LIGA being UV, is relatively inexpensive. Because heating and transmittance are not an issue in optical masks, a simple chromium mask can be substituted for the technically sophisticated X-Ray mask. These reductions in complexity make UV LIGA much cheaper and more accessible than its X-Ray counterpart.
While UV LIGA is an exceptional process to produce very thin materials, it is also limited to very thing materials. X-Ray LIGA, while not subjected to wavelength limitations of light, has the added capability of producing deep, or tall microstructures.
Photomask: Creating a mask which is applied to the substrate is the initial step. The mask blocks light from select areas of the substrate.
Substrate: A substrate such as a silicon wafer, beryllium, copper, titanium, or other material. If not already electrically conductive, the substrate is covered with a conductive base.
Exposure: The substrate is exposed within a series of established limits.
Development: After developed, the substrate is rinsed with distilled water and dried using a vacuum system.
Electroforming: Once developed we use the desired feed material, nickel, copper, gold etc. and fill the voids upward from the metalized substrate into the voids left by the removed photoresist.
Stripping: After electroforming, the resist is stripped away
This process either ends at this point or starts over for complex multilayered structures. A variety of materials can be utilized, nickel, nickel alloy, copper, gold, silver, platinum, palladium, rhodium, and, engineered plastics.
Whether you need X-Ray masks, MEMS, micro parts or complex microstructures, the LIGA process is unparalleled in its ability to produce sub-micron level accuracy micro pars and structure.
For more information or to see if LIGA is an option for your application, please contact us @ firstname.lastname@example.org