1、 TIA/EIA STANDARD FOTP-130 Elevated Temperature Life Test for Laser Diodes TIA/EIA-455-130 MARCH 2001 TELECOMMUNICATIONS INDUSTRY ASSOCIATION The Telecommunications Industry Association Represents the Communications Sector of ANSI/TIA/EIA-455-130-2001 Approved: March 13, 2001 TIA/EIA-455-130 Copyrig
2、ht Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NOTICE TIA/EIA Engineering Standards and Publications are designed to serve the public interest through eliminating misunderstandings be
3、tween manufacturers and purchasers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his particular need. Existence of such Standards and Publications shall not in any respect preclude any me
4、mber or nonmember of TIA/EIA from manufacturing or selling products not conforming to such Standards and Publications, nor shall the existence of such Standards and Publications preclude their voluntary use by those other than TIA/EIA members, whether the standard is to be used either domestically o
5、r internationally. Standards and Publications are adopted by TIA/EIA in accordance with the American National Standards Institute (ANSI) patent policy. By such action, TIA/EIA does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopting the Standa
6、rd or Publication. This Standard does not purport to address all safety problems associated with its use or all applicable regulatory requirements. It is the responsibility of the user of this Standard to establish appropriate safety and health practices and to determine the applicability of regulat
7、ory limitations before its use. (From Standards Proposal No. 4592, formulated under the cognizance of the TIA FO-2.6 Subcommittee on Reliability of Fiber Optic Systems this includes pump lasers, direct and externally modulated lasers for both digital and analog applications. Also, this test is inten
8、ded for sub-mounted (unpackaged) devices. 1.3 Background Semiconductor lasers are commonly prone to gradual degradation mechanisms that are accelerated by both temperature and optical power. Present day lasers have median lifetimes of several years even at elevated temperatures. However, devices may
9、 have material and structural defects, therefore careful purge and burn-in procedures and screening tests should be employed to eliminate potentially unreliable product from the device population. 1.4 Hazards Eye Safey Warning Care should be exercised to avoid possible eye damage from looking into t
10、he end of an energized fiber from a laser source. Especially, personnel should avoid looking into any energized fiber using any type of magnification device. 1.5 Summary The laser diode is thermally, electrically, and mechanically attached to a mount/submount/header which has had its parameters char
11、acterized. The Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIA/EIA-455-130 4optical detectors used to monitor the laser facet powers are to be configured to minimize reflect
12、ions back into the laser diode. The laser diode is driven in a Continuous Wave (CW) DC mode of operation at a specified laser facet power and at a specified laser submount temperature. The laser diode is driven either with an Automatic Power Control (APC) circuit in which the facet power is maintain
13、ed at a constant value, or with an Automatic Current Control (ACC) circuit in which the laser diode current is maintained at a constant value. Measurements of the specified device parameters should be performed periodically at room temperature (23 C +/-2 C). This data will be the basis for producing
14、 a set of descriptive reliability parameters for the product population, including the median degradation rate and lognormal standard deviation of the monitored parameter degradation rate. Care should be taken so the test atmosphere does not affect the laser diode. 2 Applicable documents Test of ins
15、pection requirements may include, but are not limited to, the most recent edition of the following documents: EIA/TIA-455-A Standard Test Procedures for Fiber Optic Fibers, Cables, Transducers, Sensors, Connecting and Terminating devices and Other Fiber Optic Components. FOTP 127 Spectral Characteri
16、zation of Multimode Laser Diodes. (EIA/TIA-455-127) FOTP 128 Procedures for Determining Threshold Current of Semiconductor (EIA/TIA-455-128) Lasers. (to be issued). EIA/TIA-610 Procedures for Calculating Optoelectronic Device Reliability. ANSI Z136.1 Safe Use of Lasers Copyright Telecommunications I
17、ndustry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIA/EIA-455-130 53 Apparatus 3.1 Fixture The apparatus used to hold the diode mount/submount/header assembly shall be temperature controlled to within +/- 2 C
18、for the duration of the test. Figure 1 shows a schematic diagram of the temperature measurements points. Figure 1. Schematic of a Typical Laser Test Configuration 3.2 Control Circuitry The laser diode control circuit shall drive the laser bias in one of the following modes: Method A Automatic Power
19、Control (APC) Method B Automatic Current Control (ACC) Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIA/EIA-455-130 6The preferred method of control is the APC mode since the
20、 device is typically operated in that fashion in use conditions. A photo detector is required to monitor the laser facet power level to provide feedback in the APC control mode. It is recommended that the control circuit for the device include protection features such as current limits, soft start c
21、ircuitry, ESD protection, and isolation, both electrically and thermally, from neighboring devices. 3.3 Optical Detectors The optical detectors for monitoring the facet output power over time shall be appropriate for the specific application. 3.4 Characterization Test Set A test set capable of measu
22、ring the required parameters in-situ shall be available to characterize the laser at specified intervals during the test. 4 Sampling Specimens are selected by a random sampling so as to represent the standard manufactured product. Appropriate handling precautions shall be used. The minimum sample si
23、ze for an aging study is 10 devices for 10,000 hours. Otherwise, the minimum sample shall be 25 devices. Larger sample sizes are recommended for improved confidence in the estimated reliability calculations. 5 Procedure 5.1 Initial Characterization The laser diode shall be fully tested in accordance
24、 with the detailed test specification. The laser diode shall be initially tested on a calibrated test set traceable to National Institute of Standards and Technology (NIST). This test set shall be available upon the completion of the aging test. This test is a complete characterization of the device
25、 in accordance with aforementioned detailed test specification and is typically only done before and after the aging test. A method for Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from I
26、HS-,-,-TIA/EIA-455-130 7determining the change, in time, of the test set shall be established to compensate for any test set drift affecting the aging data. 5.2 Aging procedure and interim measurements The device shall be attached to an external heat sink. Thermal compound may be required to provide
27、 adequate contact to the heat sink fixture. The laser diode shall be biased to the specified operating point. The device and heat sink/source shall be brought to thermal equilibrium at the specified heat sink temperature. The device shall be operated isothermally in a DC mode and data acquired at sp
28、ecified time intervals. If only one facet is in-situ monitored, either the facet with the highest light level or the facet to be coupled to the optical fiber shall be monitored. As a minimum the following parameters shall be measured at specified intervals (not less than one measurement every 24 hou
29、rs): If Laser forward current Pa Facet a power level Pb Facet b power level Tdevice Device Temperature time Time under test The complete list of parameters to be measured shall be specified in the appropriate detail test specification. The device temperature, Tdevice, should be measured as close to
30、the laser diode as possible, and it is advantageous to measure the temperature of each device under test. 5.3 Final characterization The laser shall be removed from the aging rack after the required length of time. If the in-situ data acquisition method is used, a final data point shall be recorded
31、before removing the laser from the aging rack. The device shall be retested using the same test set as used for the initial test, along with the same set of controls or standards, if functional performance data other than the degradation parameters are required. 5.4 Measurements The appropriate numb
32、er of points to be taken during the duration of the test shall be Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIA/EIA-455-130 8sufficient to perform a linear regression fit
33、of the monitored parameter vs time and obtain an estimate of the degradation rate for each device. The determination of the number of data points to take during the life test should take into account the noise of the measurement, and noise of the control circuitry, such that a low aging rate can be
34、resolved. 5.5 Test Conditions The test shall be performed according to Table 1, below, for the duration at the temperature specified under the specific condition. For example the conditions specified for an 85 C test for 10,000 hours would be “Bc“ TABLE 1: AGING CONDITIONS 6 Calculations _ The acqui
35、red data shall be analyzed according to the method described in EIA/TIA-610. CONDITION TEMP ( C) A 70 B 85 C Customer Specified or per detail spec. CONDITION Specified TIME (HOURS) a 2,000 b 5,000 c 10,000 d Customer Specified or detail spec. Copyright Telecommunications Industry Association Provide
36、d by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIA/EIA-455-130 97 Documentation 7.1 The following data shall be supplied for sample tested and for each laser diode at the conclusion of each life test. For the sample tested: 7.1.1 Tes
37、t condition (Time and Temperature from Table 1) 7.1.2 Date, title of test, FOTP used, specimen ID 7.1.3 Control mode for life testing (APC or ACC) 7.1.4 Parameters measured at intermediate points in time 7.1.5 Frequency of data monitoring 7.1.6 Facet optical power 7.1.7 Duration of test 7.1.8 Aging
38、temperature C (temperature under which aging is tests are conducted) 7.1.9 Test temperature C (temperature at which the laser characterizations are made) 7.1.10 Numerical Aperture of the Detector For each laser diode: 7.1.11 Initial measurements 7.1.12 Final measurements Copyright Telecommunications
39、 Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-TIA/EIA-455-130 107.1.13 Intermediate measurements 7.1.14 Linear aging rate of specified parameters 7.2 United States military applications require that the
40、following information also be reported for each test. For other (non-military) applications, this information need not be reported but shall be available for review upon request. 7.2.1 Personnel and test dates. 7.2.2 Test equipment and date of latest calibration. Copyright Telecommunications Industr
41、y Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Copyright Telecommunications Industry Association Provided by IHS under license with EIANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
