Sensor Package Notch Region for Overmold Alignment

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing sensor assemblies require a separate support or carrier during overmolding, increasing complexity and cost, and are prone to delamination, which can lead to reliability issues, especially in harsh environments.

Innovation Solution

A sensor package with a notch region for alignment and secure retention during overmolding, eliminating the need for a premolded support by using an alignment tool, and integrating connector pins for protection from external contaminants.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a separate support or carrier is used during overmolding to retain the sensor package, then the sensor package can be securely retained in position within the mold cavity, but the complexity and cost of the sensor assembly increases

Engineering Contradiction:
Improveretention stabilityVSAvoidassembly complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention extracts and eliminates the separate support or carrier component from the sensor assembly. Instead of using a distinct retention structure, the sensor package is directly overmolded within the mold cavity, removing the intermediate support element that added complexity and potential failure points.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The invention merges the sensor package retention function directly into the overmolding process. The mold cavity itself serves as the retention structure, combining the molding operation with the retention function, thereby eliminating the need for a separate support component.

Inventive Principle:
Principle #5Merging (Combining)

2Reliability

If a separate support or carrier is used during overmolding, then the sensor package can be retained in position, but delamination can occur between the support and overmold material enabling external contaminants into the sensor assembly

Engineering Contradiction:
Improveretention stabilityVSAvoidcontaminant ingress
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The invention removes the separate support component that creates delamination interfaces. By eliminating this intermediate layer, the potential pathway for contaminant ingress through delamination is removed, resulting in a more sealed and reliable sensor assembly.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The overmold material directly encapsulates the sensor package in a continuous, seamless shell without intermediate layers. This direct encapsulation creates a uniform protective barrier that prevents contaminant ingress, as there are no interfaces where delamination and contamination could occur.

Inventive Principle:
Principle #30Flexible shells and thin films

3Ease of manufacture

If a separate support is overmolded with the sensor package, then the sensor assembly can be formed, but the fabrication process becomes more complex and costly

Engineering Contradiction:
Improveassembly formationVSAvoidfabrication efficiency
Core Design Contradiction:
Ease of manufactureVSProductivity

Solution Approach 1:

The invention extracts the separate support component from the fabrication process, reducing the number of parts that need to be assembled and overmolded. This simplification directly reduces fabrication complexity and associated costs while maintaining the ability to form the sensor assembly.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The sensor package is positioned and secured in the mold cavity before the overmolding process begins, using the mold cavity structure itself rather than a separate support. This preliminary positioning eliminates the need for subsequent support removal or additional assembly steps, improving fabrication efficiency.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP3683826B1Sensor package, sensor assembly, and method of fabrication
Publication Date: 2023.06.21 NXP BV
  • EP3683826B1 patent drawingFigure 1~3
  • EP3683826B1 patent drawingFigure 4~5
  • EP3683826B1 patent drawingFigure 6~7

AI summary

A sensor package (20) includes a sensor die (22), connector pins (32, 34) connected to the sensor die, and a housing (42) in which the sensor die is located. The housing has first and second surfaces (44, 46) spaced apart from one another by first, second, third, and fourth sidewalls (48, 50, 52, 54). The connector pins extend from the first sidewall, and the housing includes a notch region (56) extending into the first surface of the housing such that a material portion of the housing is absent at the first sidewall and at the first surface of the housing. A method (90) for forming a sensor assembly (60) includes retaining (98) the sensor package in a cavity (106) of a mold tool (104) by receiving an alignment bar (84) of an alignment tool (80) in the notch region and performing (110, 116) an overmolding process to fill the cavity with an overmold material (70). The alignment bar is configured to hold the sensor package in the mold tool during overmolding.