Specific Process Knowledge/Characterization/Dektak XTA

Dektak XTA stylus profiler

The Dektak XTA stylus profiler from Brüker is used for profiling surfaces of samples with structures in the micro- and nanometer range. The size of the structures that can be measured is limited by the tip dimensions.

A profile measurement can be done across a specific structure by using a high magnification camera to locate the structure. It is also possible to program the stylus to measure in several positions, defined with respect to some deskew points. Stress measurements of thin films can be done by measuring the wafer bow. However, for predefined measurement programs or stress measurements, we recommend the P17 profiler - see next section.

The user manual, quality control procedure and results, technical information and contact information can be found in LabManager:

Dektak XTA in LabManager

Info about measurement accuracy can be found here.

Equipment performance and process related parameters

Purpose	Profiler for measuring micro structures	Single line profiles Wafer mapping Stress measurements by measuring wafer bow Surface roughness on a line scan
Performance	Scan range x y	Line scan x: 50 µm to 55 mm in a single scan, up to 200 mm with stiching
	Scan range z	50 Å to 1 mm
	Resolution x y	Down to 0.003 µm theoretically, in practice limited by the tip radius
	Resolution z	1 Å, 10 Å, 80 Å or 160 Å (for ranges 65 kÅ, 655 kÅ, 5240 kÅ and 1 mm respectively)
	Height accuracy z (95 % confidence)	~ 2 % for a 1 µm step with the smallest measurement range and ~ 1 % for a 25 µm step for well-defined steps that are easy to measure (read about reducing and estimating the measurement uncertainty here)
	Max scan depth as a function of trench width W	1.2*(W[µm]-5µm)
Hardware settings	Tip radius	5 µm 45^o cone
Substrates	Substrate size	Up to 6"
	Substrate materials allowed	All materials that do not stick to the tip or leave residues on the chuck For very soft polymers we recommend the Dektak 150, see below