AFM

Atomic Force Microscopy(AFM)

 
Atomic force microscopy (AFM) use a special small probe to measure certain interactions between the probe and the sample surface, such as tunneling current, atomic force, magnetic, electromagnetic near field, etc., and use one having a three-axis piezo on the sample surface to scan the sample surface. While scanning ,the vertical axis piezo is able to fine-tune the feedback circuit, so that interaction between the probe and the sample is maintained fixed during the scanning process. The distance between the probe tip and the surface is in a few to several hundred a ° (10-10m) , as long as the recording of the vertical distance, we are able to obtain an image map, these data can be used to show the sample surface characteristic. Most of AFM probes made from the silicon, the tip radius of curvature of about 10nm, is an important research tool for microscopic surface structure.

 

 

Conductive Atomic Force Microscopy (CAFM)

 
Conductive Atomic Force Microscopy (CAFM) is to add a set of current amplifier into the AFM microscope, then using Contact Mode to scan the test sample surface, while obtaining the height of the signal, if the sample surface can create current, the probe will also get the current signal. Using CAFM to obtain the height and current distribution of sample surface, and we can compare and identify the location of electrical abnormalities and also can get the current / voltage curve (IV curve) further on a specific point.

 

 

Equipment

 

Figure. VEECO INNOVA SPM (Atomic force)

 

 

Specification

 

▪  XY > 90um, Z > 7.5um 
▪  Open-Loop scanner: XY > 5um, Z > 1.5um
▪  Sample size: X-45mm x Y-45mm x Z-18mm   
▪  Motorized Z Axis stage: Z Travel:18mm 
▪  Resolution: <2um with standard 10x objective  

 

 

Applications of AFM

 

1. Material surface topography


Data storage device surface topography


LED surface topography

 

 

Applications of CAFM

 

1.Failure localization (Higher resistance/Junction leakage/Gate oxide leakage)

2.Identify Contact  types (P+/N+/Poly contact) 

3.I/V curves measurement

 

Case 1: Failure localization by CAFM,current map identify the abnormal poly

Case 2 : Failure localization by CAFM,compare the topography and current map

 

current map

 

 

topography

 
 

TEM sample preparation after CFAM failure localization

 

 

 


 

Eng. Contact Window

Ms.Huang  ext.6218

E-mail: huini_huang@msscorps.com