Auger analysis of thick silver films and of silver layers grown on copper

1981 ◽  
Vol 82 (2) ◽  
pp. 165-177 ◽  
Author(s):  
Y. Namba ◽  
R.W. Vook
Keyword(s):  
Author(s):  
Joseph D. C. Peng

The relative intensities of the ED spots in a cross-grating pattern can be calculated using N-beam electron diffraction theory. The scattering matrix formulation of N-beam ED theory has been previously applied to imperfect microcrystals of gold containing stacking disorder (coherent twinning) in the (111) crystal plane. In the present experiment an effort has been made to grow single-crystalline, defect-free (111) gold films of a uniform and accurately know thickness using vacuum evaporation techniques. These represent stringent conditions to be met experimentally; however, if a meaningful comparison is to be made between theory and experiment, these factors must be carefully controlled. It is well-known that crystal morphology, perfection, and orientation each have pronounced effects on relative intensities in single crystals.The double evaporation method first suggested by Pashley was employed with some modifications. Oriented silver films of a thickness of about 1500Å were first grown by vacuum evaporation on freshly cleaved mica, with the substrate temperature at 285° C during evaporation with the deposition rate at 500-800Å/sec.


1998 ◽  
Vol 77 (5) ◽  
pp. 1427-1436
Author(s):  
L. Kaplan, A. Shehter, Y. Lereah, H.Ta

Author(s):  
C.Q. Chen ◽  
G.B. Ang ◽  
Z.X. Xing ◽  
Y.N. Hua ◽  
Z.Q. Mo ◽  
...  

Abstract Several product lots were found to suffer from data retention failures in OTP (one time program) devices. PFA (physical failure analysis) was performed on these devices, but nothing abnormal was observed. Cross-sectional TEM (transmission electron microscopy) revealed no physical defects or abnormal CDs (critical dimensions). In order to isolate the failed layer or location, electrical analysis was conducted. Several electrical simulation experiments, designed to test the data retention properties of OTP devices, were preformed. Meilke's method [1] was also used to differentiate between mobile ion contamination and charge trap centers. Besides Meilke's method, a new electrical analysis method was used to verify the analysis results. The results of our analysis suggests that SiN charge trap centers are the root cause for the data retention failures, and the ratio of Si/N is the key to charge trap center formation. Auger analysis was used to physically check the Si/N ratio of OTP devices. The results support our hypothesis. Subsequent DOE (Design Of Experiment) experiments also confirm our analysis results. Key Words: OTP, data retention, Non-visible defect, AFP, charge trap center, mobile ion.


2018 ◽  
Author(s):  
W.F. Hsieh ◽  
Henry Lin ◽  
Vincent Chen ◽  
Irene Ou ◽  
Y.S. Lou

Abstract This paper describes the investigation of donut-shaped probe marker discolorations found on Al bondpads. Based on SEM/EDS, TEM/EELS, and Auger analysis, the corrosion product is a combination of aluminum, fluorine, and oxygen, implying that the discolorations are due to the presence of fluorine. Highly accelerated stress tests simulating one year of storage in air resulted in no new or worsening discolorations in the affected chips. In order to identify the exact cause of the fluorine-induced corrosion, the authors developed an automated inspection system that scans an entire wafer, recording and quantifying image contrast and brightness variations associated with discolorations. Dark field TEM images reveal thickness variations of up to 5 nm in the corrosion film, and EELS line scan data show the corresponding compositional distributions. The findings indicate that fluorine-containing gases used in upstream processes leave residues behind that are driven in to the Al bondpads by probe-tip forces and activated by the electric field generated during CP testing. The knowledge acquired has proven helpful in managing the problem.


Author(s):  
Hua Younan

Abstract In wafer fabrication (Fab), Fluorine (F) based gases are used for Al bondpad opening process. Thus, even on a regular Al bondpad, there exists a low level of F contamination. However, the F level has to be controlled at a lower level. If the F level is higher than the control/spec limits, it could cause F-induced corrosion and Al-F defects, resulting in pad discoloration and NSOP problems. In our previous studies [1-5], the theories, characteristics, chemical and physical failure mechanisms and the root causes of the F-induced corrosion and Al-F defects on Al bondpads have been studied. In this paper, we further study F-induced corrosion and propose to establish an Auger monitoring system so as to monitor the F contamination level on Al bondpads in wafer fabrication. Auger monitoring frequency, sample preparation, wafer life, Auger analysis points, control/spec limits and OOC/OOS quality control procedures are also discussed.


2020 ◽  
Vol 82 (3) ◽  
pp. 295-302
Author(s):  
E. V. Poleeva ◽  
A. T. Arymbaeva ◽  
O. A. Bulavchenko ◽  
P. E. Plyusnin ◽  
M. G. Demidova ◽  
...  

2005 ◽  
Vol 480-481 ◽  
pp. 287-292 ◽  
Author(s):  
S.E. Paje ◽  
F. Teran ◽  
J.M. Riveiro ◽  
J. Llopis ◽  
M.A. García ◽  
...  

In this research we study optical absorption and morphology of silver films prepared with a sputtering method. Silver granular films are obtained on a glass substrate for films with thickness smaller than about 60 Å. Superficial silver clusters of around 100 nm in diameter are clearly seen in the atomic force micrographs. The absorption of these samples are characterized by plasmon excitation in the 450-650 nm spectral range, which differs from the known excitation of silver nanoparticles fabricated by different techniques. The optical absorption of silver granular films depend on sputtering conditions like substrate temperature or deposition rate and correlates with the surface morphology.


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