An Introduction to mems (Micro-electromechanical Systems)

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for exposure to X-rays has been developed and is known as SLIGA (Sacrificial LIGA) [31].  

It replaces the thick PMMA photoresist with polyimide as the electroplating mould, thus 

enabling compatible conventional IC batch processing.  HARM production methods have 

provided radically new ways to produce micromachined parts for MEMS devices at relatively 

low cost.  In particular, techniques such as SLIGA enable the production of MEMS 

components with much lower manufacturing infrastructures in terms of investment, facilities 

and access to advanced materials and technology. 

Figure 24.  The LIGA process [3]. 

Other microreplication techniques can be combined to generate a preform for the tool insert.  

which includes electric discharge machining (EDM) and diamond milling.  EDM is a 

relatively new approach that uses machine shop production techniques and offers the 

capability to make parts out of most conductive materials.  Unfortunately, as a spark erosion 

technique, it is slow and not ideal for batch processing but has found many applications for 

MEMS prototype production.  For example, EDM was used for the micromachining of the 

DENSO Micro-car previously shown in Figure 14.