idw – Informationsdienst Wissenschaft

Nachrichten, Termine, Experten

Grafik: idw-Logo
Science Video Project
idw-Abo

idw-News App:

AppStore

Google Play Store

Veranstaltung


institutionlogo


14.02.2024 - 14.02.2024 | Online

Backside analysis to identify a package related failure mode at an automotive device

The expert session is part of our Materials Insights 23 | 24 series in which we introduce some of the latest highlights of our research focused on current and future needs in industry. Each session provides a 20 minute presentation from one of our experts and 20 minutes of discussion with the interested parties from industry and science.

This backside analysis strategy to identify a package related failure mode at an automotive magnetic sensor device is explained in this session.

Integrated circuits (IC) used in automotive applications must be produced under high quality standards. To achieve this goal each single fail from qualification or also field application must be traced down to its physical failure root cause to increase the overall device reliability. In most cases the failure analysis (FA) strategy of IC related defects is straight forward by electrical testing, followed by defect localization and finally destructive physical analysis to identify the defect structure and derive the root cause of the electrical malfunction.

In some cases, such a strategy is not straight forward, especially if the failure site cannot be exactly located or if the IC-package interaction causes the failure mode.

In this work we will demonstrate a failure root cause analysis of an automotive magnetic field sensor which fails by a simple electrical short between 2 metal layers. Over time a conductive path is created and at a certain resistance the devices fail with increases their power consumption. This could be shown several times, but the question stays unanswered over a longer time regarding the primarily root cause. There are different hypotheses under discussion, for example electrostatic discharge, package issues as well as imprints induced by probe tools.

In a standard FA procedure, the package is fully removed above the IC to get access to its functional surface structure. Then further localization and preparation steps are following. At this specific failure mode, the original root cause could not be identified from frontside despite many trials, that’s why it was decided to turn the preparation starting from backside without removing the package at the frontside. The real challenge was that the failing position could not be localized in detail as normally done by emissions microscopy or OBIRCH. Due to the electrical behavior of the sensor and the experiences collected by many fails before the position could be estimated and correlated to a several 10µm long metal network.

To get access to the ROI the Si substrate was mechanically thinned down to several µm thickness. After this the remaining silicon was removed by Xe-Plasma FIB trenching down to the active IC structure. The interface near opened structures are used for superposition. Then the metal network was cut by Ga-FIB at several positions and investigated by passive voltage contrast to identify the shorted part of the affected network.

Finally, the remaining shorted metal lines were screened by forwarding FIB cross sectioning under SEM observation till irregularities (delamination, cracks) could be found in the IC structure. The defect origin could be identified due to the preserved mould compound on top of the IC. A large filler particle touches the IC passivation at the position of the cracks. Due to mechanical stress during the moulding process these cracks were initiated, later metal was migrating into these cracks forming an electrically conductive path between metal 1 and 2. The same failure mode could be verified at several sensor devices.

Hinweise zur Teilnahme:
Participation is free, registration is required.

Termin:

14.02.2024 14:00 - 14:45

Anmeldeschluss:

14.02.2024

Veranstaltungsort:

Online
06120 Online
Sachsen-Anhalt
Deutschland

Zielgruppe:

Wissenschaftler, jedermann

Relevanz:

international

Sachgebiete:

Elektrotechnik, Maschinenbau, Verkehr / Transport, Werkstoffwissenschaften

Arten:

Seminar / Workshop / Diskussion, Vortrag / Kolloquium / Vorlesung

Eintrag:

25.01.2024

Absender:

Susann Dohmhardt

Abteilung:

Presse- und Öffentlichkeitsarbeit

Veranstaltung ist kostenlos:

ja

Textsprache:

Englisch

URL dieser Veranstaltung: http://idw-online.de/de/event76105


Hilfe

Die Suche / Erweiterte Suche im idw-Archiv
Verknüpfungen

Sie können Suchbegriffe mit und, oder und / oder nicht verknüpfen, z. B. Philo nicht logie.

Klammern

Verknüpfungen können Sie mit Klammern voneinander trennen, z. B. (Philo nicht logie) oder (Psycho und logie).

Wortgruppen

Zusammenhängende Worte werden als Wortgruppe gesucht, wenn Sie sie in Anführungsstriche setzen, z. B. „Bundesrepublik Deutschland“.

Auswahlkriterien

Die Erweiterte Suche können Sie auch nutzen, ohne Suchbegriffe einzugeben. Sie orientiert sich dann an den Kriterien, die Sie ausgewählt haben (z. B. nach dem Land oder dem Sachgebiet).

Haben Sie in einer Kategorie kein Kriterium ausgewählt, wird die gesamte Kategorie durchsucht (z.B. alle Sachgebiete oder alle Länder).