Hi Essaid:

You may find useful to read this work, on the simulation of a n-type HPGe detector. A study on the effect of dead layers on the simulation results is included.

N.L. Maidana, V.R. Vanin, J.A. García-Alvarez, M. Hermida-López, and L. Brualla, “Experimental HPGe coaxial detector response and efficiency compared to Monte Carlo simulations,” Appl. Radiat. Isot. 108, 64–74 (2016).

 Regards,

Marcelino

http://www.sciencedirect.com/science/article/pii/S0969804315303407

Hi Marceleno 

Thank you for your answer, there are some works where the authors found a different results. here are some ones:

Alpha-event characterization for germanium detectors (Tesis) - Garbini Lucia - Munich 2016

S. Hurtado, M. García-León , R. García-Tenorio ., Monte Carlo simulation of the response of a germanium detector for low-level spectrometry measurements using GEANT4. Applied Radiation and Isotopes : 61 (2004) 139–143

Yadong Ding, Qingbin Wang, Zhongjian Ma, Qingjiang Zhang,MingyangYan ., HPGE detector application on monitoring enviremental samples aroud the accelerator. WEPOR024 -Proceedings of IPAC2016, Busan, Korea

Regards

It is not possible to know with certain the dead layer thickness. You can use the MCNP to estimate it. Note that this dead layer is not a real physical thickness, this should be considered as the degradation of the crystal as a entirety.

It is known that the "dead layer" value after 20 years of use increases. But it is not possible to know how much increases. If the detector does not turn off the dead layer not increase. The thermal cycle can increase the dead layer. On the other hand, if the MCNP determines relatively well in a range

Hi.

Before you start adding additional dead layers to the from of an n-type Ge have you considered increasing the thickness of the end-cap (DurAl normally) of the detector ?

Regards

Hi Karl

in reality I have used the manufacturer data, i have changed just the dead layer thickness to study the energies

Hi,

Do you know whether the detector has standard or reversed contacts ? 

So essentially what you have done is to swap your n+ (~0.3 um B) and p+ (~0.5 mm thick Li) contacts ? 

I think that in addition to these two contacts there would a layer (interface) of passivated Ge. Effectively another dead layer. At the Li junction this is  ~0.3 mm. I do not know what it would be at the B implant junction.

Also, what have you used as the end-cap material ? Aluminium or Dural ? Dural is an alloy that is slightly denser than Al and has some higher Z materials (Cu and Mn)

regards

Hi,

the detector is reversed HpGe n-type, has a n+ like an out side contact (lateral dead layer =0.3 um), and the end-cup material is Aluminium.

in some papers, i found that the dead layer for this type of detectors will can't increase. in others i found the oposite. but in the case of our study, i fond it to be 60um laterally and 250 um in the front part. 

during the discussion with some professors, they commented that what we have found is not correct.

what's your opinion Karl?

Regards

Can anybody answer this Q

https://www.researchgate.net/post/Why_n_contact_of_p_type_Ge_is_700um_thick_compared_to_p_contact_of_n_type_Ge_only_03um

Dear David, You mean to say the process of adding the contact is different. Li is added by diffusion process but B is added by implantation. In Ion implantation we can achieve thin contact, but in diffusion we can get only Thick contact. Fine. It is liks DJD vs PIPS detector for alpha. Can you tell me why Li is also not added as contact by Ion implantation method?