Micro-sectioning

In failure analysis the primary use of a laser cutter is micro-sectioning to isolate portions of a circuit for further analysis or to remove passivation materials such as silicon nitride and/or silicon dioxide to allow electrical contact with conductive layers. Different wavelengths of laser light will remove certain materials more efficiently than others. By using a number of wavelengths of light a laser cutter can selectively remove materials.

Different wavelengths are used to cut different materials typically associated with semiconductor and MEMS structures.

Material Groups	Near Infrared (1064nm)	Green (532nm)	Near UV (355nm or 266nm)
Metal/Conductors	Aluminum	Aluminum
	ITO	ITO
	Chrome	Chrome
		Ni-Chrome
		Ti-Tungsten
		Copper
		Gold
Insulators		Silicon Nitride	Silicon Nitride
		Silicon Dioxide
			Polyimide
			Teflon
			Kapton
Semiconductors		Polysilicon	Polysilicon

Micromanipulator sells EzLaze and QuikLaze laser cutters from New Wave Research which may be ordered with either one, two or three wavelengths of light; Near IR(1064nm), Green (532nm), and Near UV (355nm or 266nm).

Cut Size (Single Pulse)
Minimum

• 1x1µm Green or UV with 100x objective
• 2x2 µm NIR with 100x objective

Maximum

• 50x50 µm Green or NIR with 50x objective
• 40x40 µm NUV3 (355nm) with 50x objective
• 30x30 µm NUV4 (266nm) with 50x objective

Vibration

In order to successfully use a laser cutter especially for fine cutting in the 1 µm range a highly stable and vibration free probe station is required. The 2200, 4000, 8000, and 9000series stations all are designed to hold and position heavy microscopes and laser cutters. The natural vibration damping designs of Micromanipulator stations may be enhanced with a wide range of vibration isolation tables and station enclosures.

Other Uses of Laser Cutters

In some cases laser cutters may also allow the creation or reforming of electrical connections by carefully heating the metal around small gaps and allowing the metal to flow together.

The low power laser cutter light may also be used in stimulation of electrical circuits in OBIRCH, LIVA and TIVA testing. These tests generally are used with semiautomatic stations to automate the movement of the light spot over the circuit.