1. Introduction

In microelectronics we are aware of the fact that everything is becoming smaller and smaller. This trend influences more and more mechanical components and complete machines and systems. In the down scaling of systems and their components the limits of conventional manufacturing techniques are reached. This initiates the improvement of conventional methods and further development of new techniques. For the shaping of micro parts the main area for developments lies within the process step of injection molding.

2. Definition of micro parts and examples

With regard to micro injection molding different concepts of a micro part exist. It is very important to distinguish between these concepts because different production equipment and processing are connected with each of them. The following types of parts related to the concept of "micro" exist [KUK 98, REI 98, KUK 00]:

• micro-injection molded parts,

• injection molded parts with micro-structured areas ("Micro on Macro").

A micro-injection molded part is defined by a volume of less than around 0,3 cm ³. This limit is set by injection molding machines. It defines the lower limit of shot volumes realizable by standard machines. Such parts may, but need not, have dimensions in the range of micrometers. Examples are shown in Figure 1.

Figure 1: Examples of micro-injection molded parts

The second type are injection molded parts with micro-structured areas (short name: "Micro on Macro"). These cover injection molded parts of conventional dimensions with areas having dimensions...