A Demonstration on the Effectiveness of Wafer-level Thermal Microscopy as A Complementary Tool to Photon Emission Microscopy Using MBIST Failure Debug

2015 ◽

Author(s):

S.H. Goh ◽

G.F. You ◽

Alan Tan ◽

C.V. Bharadwaj ◽

Hu Hao ◽

...

Keyword(s):

Thermal Emission ◽

Photon Emission ◽

Fault Localization ◽

Optical Resolution ◽

Fault Isolation ◽

Thermal Microscopy ◽

Emission Microscopy

Abstract Unlike photon emission microscopy which is usually the first go-to technique in tester-based or dynamic electrical fault localization, infrared thermal microscopy does not play a similar routine role despite its comparable ease in application. While thermal emission lacks in optical resolution, we demonstrate superior sensitivity and accuracy over photon emission on dynamic fault localization of backend-of-line short defects.

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Analysis of Delta Iddq Soft Fails on Pass Chips

ISTFA 2006: Conference Proceedings from the 32nd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2006p0305 ◽

2006 ◽

Author(s):

I. Österreicher ◽

S. Eckl ◽

B. Tippelt ◽

S. Döring ◽

R. Prang ◽

...

Keyword(s):

Failure Analysis ◽

Failure Mode ◽

Photon Emission ◽

Complete Analysis ◽

Functional Tests ◽

Analysis Techniques ◽

Atomic Force ◽

Current Consumption ◽

Emission Microscopy ◽

Failure Localization

Abstract Depending on the field of application the ICs have to meet requirements that differ strongly from product to product, although they may be manufactured with similar technologies. In this paper a study of a failure mode is presented that occurs on chips which have passed all functional tests. Small differences in current consumption depending on the state of an applied pattern (delta Iddq measurement) are analyzed, although these differences are clearly within the usual specs. The challenge to apply the existing failure analysis techniques to these new fail modes is explained. The complete analysis flow from electrical test and Global Failure Localization to visualization is shown. The failure is localized by means of photon emission microscopy, further analyzed by Atomic Force Probing, and then visualized by SEM and TEM imaging.

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A Study of Clustering for the Enhancement of Image Resolution in Dynamic Photon Emission

ISTFA 2019: Conference Proceedings from the 45th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2019p0068 ◽

2019 ◽

Author(s):

S. Chef ◽

C. T. Chua ◽

C. L. Gan

Keyword(s):

Signal To Noise Ratio ◽

Photon Emission ◽

Optical Signal ◽

Image Resolution ◽

Time Dimension ◽

Processing Scheme ◽

3D Space ◽

Initial Acquisition ◽

Resolution Limits ◽

Emission Microscopy

Abstract Limited spatial resolution and low signal to noise ratio are some of the main challenges in optical signal observation, especially for photon emission microscopy. As dynamic emission signals are generated in a 3D space, the use of the time dimension in addition to space enables a better localization of switching events. It can actually be used to infer information with a precision above the resolution limits of the acquired signals. Taking advantage of this property, we report on a post-acquisition processing scheme to generate emission images with a better image resolution than the initial acquisition.

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WLCSP Laminate Removal Using NIR Laser

10.31399/asm.cp.istfa2018p0486 ◽

2018 ◽

Author(s):

Chun Haur Khoo

Keyword(s):

Near Infrared ◽

Laser Energy ◽

Photon Emission ◽

Mechanical Damage ◽

Consumer Products ◽

Fault Isolation ◽

Wafer Level ◽

Isolation Technique ◽

Laminate Layer ◽

Nir Laser

Abstract Driven by the cost reduction and miniaturization, Wafer Level Chip Scale Packaging (WLCSP) has experienced significant growth mainly driven by mobile consumer products. Depending on the customers or manufacturing needs, the bare silicon backside of the WLCSP may be covered with a backside laminate layer. In the failure analysis lab, in order to perform the die level backside fault isolation technique using Photon Emission Microscope (PEM) or Laser Signal Injection Microscope (LSIM), the backside laminate layer needs to be removed. Most of the time, this is done using the mechanical polishing method. This paper outlines the backside laminate removal method of WLCSP using a near infrared (NIR) laser that produces laser energy in the 1,064 nm range. This method significantly reduces the sample preparation time and also reduces the risk of mechanical damage as there is no application of mechanical force. This is an effective method for WLCSP mounted on a PCB board.

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