Quality Grades and Reliability

Quality Grades

The available Quality Grades are defined in 3D Plus Process Identification Document. The Quality Grade of a product consists of a temperature range and a screening level.

The available temperature ranges are:

  • C : 0 °C / 70 °C
  • I : - 40 °C / + 85 °C
  • M : - 55 °C / + 125 °C
  • S : Specific on customer's demand

The available screening levels are:

  • N : Commercial
  • B : Industrial
  • S : Space as per ESA qualification

The combinations of « Temperature Range » and « Screening level » allow serving a broad range of applications and customers’ requirements.

For Space applications, «-IB» Quality Grade is used for Engineering Models and «-IS» or «-MS» Quality Grade are used for Flight Models.

Remark:
The ESA Space qualification system being very similar to the MIL and QML standards in the USA, 3D Plus Space grade products are equivalent to MIL-PRF-38534 class K products or to QML-V products.

Screening Level description

The screening level depends on the stacking technology flow used : Standard Packages stacking (Flow 1) or Flex stacking (Flow 2).
In space terminology, Engineering Models (EM) correspond to the Industrial level and Flight Models (FM) correspond to the Space level.
It shall be noted that this screening level can be amended through a specific product specification.

Technology Flow Steps & Operations Screening Level
Flow 1 Flow 2   Commercial Industrial Space
Applicable documentation      
    Process Identification Document (PID)
    Module procurement specification    
    Module test specification
    Components and Materials procurement      
Components and Materials lots traceability    
Components and Materials Lot Acceptance Test (LAT)    
    Modules manufacturing      
Manufacturing traceability for each module lot
  Flex assembly according to PID
  Electrical test at +25°C - Go/NoGo (5) (5)
  Burn-in flex 168hrs +125°C followed by an electrical test at +25°C – Go/NoGo     (3)
  Flex Precap visual inspection before stacking    
Module Manufacturing according to the PID
Electrical test at +25°C - Go/NoGo
Modules screening      
    Stab. Bake 72hrs +125°C  
    Thermal cycles (x10) –55°C/+125°C  
    Electrical test at +25°C pre burn-in with R&R    
    Burn-in 168hrs or 240hrs / +125°C   (2) (4)
    Electrical test at Tmin, +25°C, Tmax, (8)   (Go/NoGo) (R&R)
    Parameters drift calculation at +25°C    
    P.D.A. calculation     (6)
    Final external visual inspection
    Dimensions measurements (3 modules)
Modules serialization   (1)
Module Lot Acceptance Test - (7)      
    Life test 1000hrs / +125°C    
    Electrical test at Tmin, +25°C, Tmax, Post life test with R&R – (8)    
    Parameters drift calculation à +25°C    
    Final external visual inspection    
    Final DPA (1 module)    
    Quality Assurance      
Customer source inspection    
Documentation delivered Delivery Note Delivery Note +CoC Delivery Note +EIDP

(1) If option 1 is selected, modules are serialized and components lots traceability is kept through the flow.
(2) If option 2 is selected, the modules are submitted to a burn-in 168hrs/+125°C.
(3) If option 3 is selected, a 168hrs burn-in is performed for each flex. Therefore, the module burn-in duration may be reduced to 96 hrs.
(4) If option 4 is selected, the burn-in duration is 240hrs.
(5) If option 5 is selected, each flex is electrically tested.
(6) PDA calculation is in accordance with ECSS-Q-60-05 :
- For parametric Drift failure, if the number of failed modules exceeds 5% of the number of modules submitted to burn-in and electrical measurements the lot shall be rejected.
- If the cumulative total of Parameter Drift Failures and Parameter Limit Failures exceeds 10% of the number of modules submitted to burn-in and electrical measurements, the lot shall be rejected.
(7) Modules LAT sample according to ECSS-Q-60-05 :

Module lot size Sample 1° lot Sample next lots
1 to 25 2 1
26 to 50 3 2
51 to 90 4 3
> 90 5 4

(8) Unless otherwise specified, electrical test temperatures are : Tmin=-40°C and Tmax=+85°C

Reliability and Harsh Environments

3D PLUS modules are designed to support harsh environments proved by both environmental and mechanical tests. The table below lists some tests successfully withstood by 3D PLUS modules.

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