T. O. metal can electrical test rejects

[metal ken]

Good day to all:

I'm new here.
I just want to ask what could be the cause of our electrical test rejects for T. O. metal cans.
I tried using a newer spool of gold wire (expires on a later date) against the ones that will expire on an earlier date but i still got the same result. Can someone help me on this?

Thanks in advance!

 

[Raza]

What type of that test is?
Your question may not be clear, please always elaborate to get reply quickly.

 

[metal ken]

Good day sir:

The test in particular is dark current. Id=10 nA. Our operator said we're getting higher values and sometimes the pico ammeter reads out "overflow". It's for hermetically sealed metal can packages. And basing from our customer's web site (eGTRAN), the assembled metal cans go to their products for optoelectronic applications. It's a recurring problem, not just with a certain lot. The device is PD300-001-105. I only found PD300-003-105 from the anadigics web site. (eGTRAN is formerly anadigics.) I'm new to the company. According to them, they have assembled PD300-003-105, but only as a qual lot. For whatever reason, they discontinued assembly. What we're assembling up to the present is PD300-001-105. Again according to them, the problem existed before (up to now), despite of changes in materials used. There was a change in capillary to address non-sticking bond issues.

Thank you very much!

I'll try to post the process flow later as well as other parameters.

 

[Raza]

OK
But I got datasheet for only PD300-003-105 and and not for PD300-001-105. As I could understand is that the DARK current is more than it should be, is it that?. If yes,
Upload the datasheet for the same along with test procedure. I may be able to help any.
Another question, what is the material of Photo diode and in the metal can nickled inside, I mean the can inside is shining or has blackened surface ?

 

[metal ken]

Good day sir:

On the dark current, the readings measured on our tester (keithly 485 / 6485) should not exceed the value required by a certain customer. The photodiode is InGaAs, and our caps are from schott. I think the surface of the case is the same (shiny) all throughout. No special coating of some sort on the inner surface to blacken it.

 

[Raza]

You people have to search out the cause, if it is the CAN making problem or Diode material it self is not coming to the level required of the dark current. I suggest (may 100% wrong) first check it without encapsulating is the required dark current achieved ? If yes then have to look entirely into canning procedure.

 

[metal ken]

Good day sir:

Actually, our operators bond 5 to 10 units and test it for dark current before proceeding with the whole lot. So far, the readings passed. The next process would be third optical inspection, third optical inspection gate, pre-seal bake, capping / welding, helium bombing, fine leak test, gross leak test, and then the dark current test.

Thank you very much!

 

[metal ken]

Here is our process flow for our PD300-001-105.
1. 2nd Optical Inspection
2. 2nd Optical Gate
3. Die Attach
4. Die Alignment
- + / - 3 mils (x-y axis)
5. Die Attach Epoxy Cure
- Temp.: 100 deg. Celsius
- Time: 1 hr.
6. Wire Bond
7. 3rd Optical Inspection
8. 3rd Optical Gate
9. Helium Bombing
- 4 hrs. + 15 min. @ 40 - 45 psi
10. Fine Leak Test
- 5 x 10-7 atm-cc/sec min.
11. Gross Leak Test
- Galden DO2
- 125 + / - 10 deg. Celsius
12. Dark Current Test
- Supply: 5 V
- Id: 10 nA max.
...