Micromechanical device, micromechanical system, apparatus for adjusting sensitivity of a micromechanical device, method for producing a micromechanical device

#This application claims priority from German Patent Application No. 10 2007 021 920.4, which was filed on May 10, 2007, and is incorporated herein in its entirety by reference.

#The invention relates to micromechanical devices having an oscillation element and a spring portion, and for example to the adjustment of the sensitivity of the spring hardness to fabrication variations.

#Micromechanical devices with oscillatably suspended oscillation elements may be employed both as micromechanical sensors and as micromechanical actuators. The micromechanical device consisting of the spring portion and the oscillatably suspended oscillation element has an eigenfrequency or resonance frequency. In many applications, the resonance frequency of the micromechanical device is to correspond to a fixedly default frequency, in order to achieve, using the resonance increase, for example sufficient sensitivity in the case of a sensor and for example sufficient oscillation amplitude in the case of an actuator. Examples for micromechanical structures e.g. are those serving as clock transmitters in e.g. clocks, or deflecting elements such as scanner mirrors, which are used for data projection, wherein the data frequency and the oscillation frequency is to be in an fixedly default ratio. So as to keep the power needed for the oscillation generation low, such devices generally possess relatively high quality, with the result that the resonance curve is narrow and there is only very little margin in the excitation frequency when maintaining the desired oscillation amplitude.

#Embodiments of the present invention will be detailed subsequently referring to the appended drawings, in which:

#FIG. 1A shows an embodiment of a micromechanical device with an oscillation element oscillatably suspended via a spring portion.

#FIG. 1B shows embodiments of a spring portion with various trenches or trench structures.

#Before the present invention will be explained in greater detail in the following on the basis of the accompanying drawings, it is pointed out that the drawings are not to scale for better comprehensibility. Moreover, the same reference numerals are used for objects and functional units having the same or similar functional properties, with repeated description of these objects and functional units being omitted. In this context, it is further pointed out that on the one hand, unless explicitly indicated otherwise, sections referring to objects with similar or the same functional properties are interchangeable among the descriptions of the various embodiments. On the other hand, it is pointed out that by common use of a reference numeral of an object occurring in more than one embodiment it is not shown that these have identical features and properties in the various embodiments or the embodiment concerned. Common or similar reference numerals hence do not represent any indication regarding the concrete design and dimensioning.

#FIG. 1A shows an embodiment of a micromechanical device 100 with a layer 110 in which at least one slot 120 is formed to define an oscillatably suspended oscillation element 150 via a spring portion 130 (see dot-dash line) of the layer 110, wherein a trench 140 is formed in the spring portion 130 in a main surface 112 of the layer 110. The spring portion 130 has a width b and a length l.

#Thus, FIG. 1A shows an embodiment of a flexion spring, for example.